In order to solve the problem of short foresight period of deep learning algorithms in reservoir water level prediction, the LSTM-Informer reservoir water level prediction model is constructed with Wudongde Reservoir as an example, which predicts the reservoir water level in the future for 6, 12, 24, 48, and 96 steps, and compares the prediction result with those of the LSTM and Informer models. The results show that when the prediction step size is not more than 12, all three models can simulate the reservoir level well and the performance difference is not obvious, when the prediction step size is more than 12, the performance of the three models is LSTM-Informer>Informer>LSTM, and the RMSE and MAE of the LSTM-Informer model at 96 steps are 0.147 and 0.120 respectively, and the RMSE of the LSTM-Informer model is 25%, 46% and 62% lower than LSTM, and the MAE is 23%, 40% and 47% lower than LSTM, respectively. The combined model LSTM-Informer can solve the long time series reservoir level prediction problem better.

Currently, some enterprises still face problems such as unclear control responsibilities, long management hierarchy chains, and lack of joint management efforts in promoting the implementation of the safety production responsibility system. Security grid management decomposes security management responsibilities into specific areas, positions, and personnel, strengthens the execution of security management, and implements the safety production responsibility system. Xili Reservoir to Nanshan Water Plant raw water pipe project of Shenzhen Raw Water Company was taken as an example, and the effective operation mode of safety grid management in the field of engineering construction was explored from the characteristics of safety grid management “fixed grid, fixed personnel, and fixed responsibility” and the working mechanism of “clear responsibility, performance, and evaluation”. Secondly, specific work ideas on how to carry out smart supervision in the follow-up of work safety grid was put forward. A new model of “Internet plus+grid” smart safety supervision was built to assist project safety management. Research findings provide a scientific management method and evaluation mechanism for the implementation of safety production responsibility system in construction projects, which is of great significance for improving the safety management level of projects.

BIM technology, as an important technical means to promote the digitalization and intelligentization of water conservancy project construction, has become a strong support for the high-quality and innovative development of the industry. With the continuous deepening of BIM technology application in the survey and design of water conservancy projects, limited by the complexity of the survey and design business processes of water conservancy projects, there are still significant bottlenecks in the promotion of BIM forward collaborative design and related applications, [Results]ing in insufficient value of BIM in the design stage. In order to effectively promote the application of BIM forward collaborative design in the industry, this paper proposes a forward collaborative design method for water conservancy and hydropower projects based on the 3DExperience platform by sorting out the BIM collaborative design system, summarizing the forward design operation process, and refining BIM business application scenarios. Relying on the Gongming-Qinglinjing Reservoir Connection Project in Shenzhen, the forward collaborative design application practice was carried out. Through the BIM forward design planning of the project, a multi-dimensional collaborative design system was constructed, including business collaboration between survey and design professionals, collaboration between design and computational analysis, collaboration between design and construction simulation, and collaboration between design and management. Multi-level applications such as digital survey, design management, route selection analysis, scheme optimization, engineering measurement, rapid drawing, simulation analysis, and digital delivery were achieved, effectively improving the quality and efficiency of design. This helped the project achieve the overall goal of completing feasibility studies, preliminary design, and bidding design work within one year, creating significant application value.

As an important node in the Pearl River Delta water resource allocation project, the safe operation of Luotian Reservoir is crucial for ensuring regional water supply safety and flood control system. With the passage of time and the improvement of functional standards, reservoir dams are facing problems such as high permeability of rock and soil in the dam foundation, leading to serious leakage. In order to improve the safety and stability of the dam, a systematic design scheme for dam foundation curtain grouting was proposed. Taking Luotian Reservoir as an example, the engineering overview, existing problems, leakage estimation and analysis, curtain grouting design, construction technical requirements, and common problem handling of Luotian Reservoir are introduced in detail. After the implementation of the designed dam foundation curtain grouting scheme, the leakage of the Luotian Reservoir dam was significantly improved, and the effect was significant, achieving the goal of anti-seepage reinforcement. The effectiveness and feasibility of the dam foundation curtain grouting scheme were verified. The proposed design scheme provides reference and inspiration for anti-seepage reinforcement engineering of similar dangerous reservoir dams.

With the acceleration of urbanization, the urban deep-buried water conveyance tunnel project has become an important infrastructure to solve the problem of urban water supply. However, in engineering practice, seepage problems often occur under complex geological conditions such as reservoirs, which not only affect the safety of the project, but also pose a potential threat to the environment. Based on the background of a deep buried water conveyance tunnel project in a city, the analysis and research on the seepage influence of the tunnel under the reservoir were systematically carried out. The relevant research result can provide reference for the follow-up similar engineering construction.

Reverse construction method is an unconventional construction method, generally used in special situations such as deep foundations, complex geology, and high groundwater levels. Underground structures are constructed using reverse construction method, which can reduce costs, shorten construction periods, reduce the impact on the surrounding environment, and ensure construction safety. It is an effective method for constructing high-rise basement or underground structures. However, the theoretical analysis of underground structures started relatively late, especially in terms of construction theory, which is not yet very complete. Therefore, it is necessary to conduct in-depth and detailed research on the construction process.

The flow control valve mainly achieves flow control by adjusting the valve opening. Different valve types and structural types can be selected according to different engineering characteristics, application scenarios, and pressure regulation range requirements. If the valve type is not selected properly, it not only affects the accuracy of flow control, but also causes valve vibration and noise due to cavitation problems, thereby affecting the service life of flow control valves. Therefore, it is crucial to choose the appropriate type and parameters of regulating valves based on the characteristics of the project and the usage scenario. A selection and design method were summarized for flow control valves in gravity pressurized flow engineering. A comprehensive analysis and comparison of flow control valves are conducted from several aspects such as valve type, diameter selection, installation elevation, and cavitation performance. The method has been successfully applied to the connection project between Shenzhen Gongming Reservoir and Qinglinjing Reservoir, ensuring the reliability, safety, and stability of project operation. This selection design method can provide reference for similar long-distance water transportation projects in the future, and has certain engineering application value.

The combined structure of segment-bean gravel-surrounding rock is the main bearing structure of TBM with pressure water transmission tunnel. Taking the TBM section of the water transmission tunnel in Hubei as the research object, the three-dimensional finite element numerical analysis model of segment-bean gravel-surrounding rock combined structure is established, and the internal pressure bearing characteristics of the combined structure under the influence of excavation load release are considered. The result show that considering the overall stress, joint opening and bolt stress in the case of partial excavation load release, it is more beneficial to the segment to bear the inner water pressure; the main location near the inclined bolt will affect the crack distribution; the wedge cap affects the stress distribution of the segment bolt under the inner water pressure, and the internal water pressure under the inner water pressure.

Deep buried hydraulic tunnels bear both external soil and water loads as well as internal water pressure during operation. Under high internal water pressure, the stress and deformation of their pipe structure are very complex. Relying on the Changhua River Water Resources Allocation Project in Hainan Province, the mechanical characteristics of the segment structure of high-pressure shield tunnels were explored from two perspectives: bearing different construction excavation loads and different segment assembly method. The results show:(1) The larger the excavation load borne by the pipe segment, the more obvious the “transverse elliptical” deformation of the pipe segment, and the more the circumferential stress distribution of the pipe segment tends towards a “necking” shape. The stress of circumferential bolts is related to the opening amount of pipe joints, and the distribution of pipe joint opening amount varies when bearing different construction excavation loads.(2) There is significant displacement and displacement between the staggered assembly structure rings, and the presence of longitudinal bolts and friction between the rings gives it a significant longitudinal strengthening effect.(3) Longitudinal bolts can share the stress state of circumferential bolts, and the stiffness of single ring pipe segments is significantly lower than that of multi ring pipe segments. It is recommended to use shear multi ring pipe segment structures in numerical simulations.(4) There is basically no interaction effect between the rings in the seamless structure pipe segments, and there is a process of internal force transmission in the staggered structure pipe segments, which decreases from the middle ring to both ends. Under the interaction force between the pipe segments and the action of longitudinal bolts, the stiffness of the middle ring pipe segments is improved.

In the process of urban underground rail transit engineering construction, suitable shield equipment selection is the key factor of tunnel construction, and the scientific and reasonable design of key equipment components is the core of safe and efficient shield tunneling. There are complex geological problems such as karst, composite strata and long distance hard rock along the tunnel between Shenhui Intercity Longcheng Station and Longling working well. Based on factors such as formation adaptability, construction risk, duration and cost, the type selection of 9 m shield tunneling machine is studied. The result show that EPB/TBM dual-mode shield is feasible, which could provide technical reference for similar formation shield equipment selection.

In the modern industrial environment, the field of water EPC management is faced with unprecedented complex data management and decision-making challenges. With the continuous growth of data volume, traditional data processing method have been difficult to meet the requirements of efficient and high-precision knowledge extraction and management. The construction technology of knowledge graph was discussed for water conservancy EPC enterprise management based on deep learning. Entity identification is carried out by combining BERT-BiLSTM-CRF model, and inter-entity relationship extraction is carried out by using improved BERT-BiGRU-Attention model. The knowledge graph construction and systematic analysis are carried out on the information of standards, specifications and management documents in the field of water conservancy EPC management. The result show that the entity recognition rate and relation extraction rate of the improved knowledge extraction model in the field of water conservancy engineering management are as high as 93.5% and 92.9% respectively, which significantly improves the efficiency of EPC knowledge management and lays a foundation for comprehensive knowledge application. Finally, knowledge extraction was integrated with the water conservancy EPC management platform, which has a friendly operation interface and supports dynamic knowledge update and knowledge query. To sum up, the study findings provide a dynamically updated and rich knowledge graph resource base for professionals in the field of water conservancy engineering management, enhances the complex decision-making ability in the process of EPC project management through the water conservancy EPC management platform, and promotes the intelligent management of water conservancy EPC projects.

Construction wastewater of small watersheds regulation projects cause river pollution. As a long-line project, river regulation often shows a scattered distribution, with inconvenient transportation, manual inspection is difficult to guarantee the efficiency of construction water pollution control. At present, intelligent inspection is usually used to identify floating objects, which is difficult to identify water pollution such as sewage and water bloom. This paper proposed an intelligent recognition and positioning method for anomaly images of water pollution in river regulation projects based on UAV aerial photography and deep learning. The aerial images of working area are collected by UAV inspection, and an EfficientNet-B0 model of intelligent identification and classification of construction water pollution image is established based on the MBConv module optimized by the SENet attention mechanism. Transfer learning is used to train the model, which can make the pollution-related features extracted by the model more directional, and improve the training speed and accuracy of the model. Then, the feature map of pollution area based on Grad-CAM(Class Activation Mapping) and fully connected CRF(Conditional Random Fields) can modify the misclassification area that achieve more refined fast marking and positioning of pollution area.The practical application result show that the classification accuracy of water pollution images is 98% and the evaluation index ORI of the positioning method is 96.91%. This study can provide advanced technical means for project managers to quickly control the water pollution of long-line river regulation projects.

Engineering specifications are one of the important standard documents commonly used in the construction process. Faced with these unstructured engineering specification texts, efficiently and accurately extracting relevant knowledge and presenting this knowledge in a visual format plays a significant role in improving knowledge utilization efficiency and enhancing management personnel′s understanding of engineering specification texts. A deep learning-based method was proposed for extracting knowledge from typical engineering specification texts, integrating ALBERT(A Lite Bidirectional Encoder Representation from Transformers), BiLSTM(Bi-directional Long Short-Term Memory), and CRF(Conditional Random Fields) to establish an entity recognition model for engineering specifications. The model enhances the semantic features of the text to identify entities within the engineering specifications. Additionally, it employs the Attention mechanism and BiLSTM to extract relationships from the engineering specifications and constructs an engineering specification knowledge graph based on the extracted knowledge. Using the “Construction and Acceptance Specifications for Water Supply and Drainage Pipeline Projects” as a typical example, the method was validated, yielding an F1 score of 78.18% for entity recognition, which is superior to traditional models, and an F1 score of 98.35% for relationship extraction. Leveraging this knowledge, an engineering specification knowledge graph was established. Through a knowledge graph-based global information display, specific information retrieval, the efficiency of utilizing engineering specification knowledge was improved, assisting with on-site construction.

During the construction of concrete dams, a large amount of material information expressed in unstructured text is generated, which is of great significance for engineering quality inspection and further research and development of materials. Due to the limitations of data management technology, there is a large amount of material text data stored in the form of images, which is difficult to directly edit and utilize, and cannot meet the needs of intelligent analysis and management of concrete dam material data. In addition, there is currently a lack of intelligent information extraction mechanisms for massive material text data, making it difficult to efficiently obtain key information from the text. An intelligent interpretation method was proposed for concrete material text based on image data, which identifies text information in image data and improves the detection and recognition efficiency of inclined material text. Based on the interpreted image data, starting from the multi perspective text feature relationship, using MMR algorithm as the framework, combined with BERT model and TF-IDF algorithm, considering the importance of text semantics and professional terminology, a set of intelligent analysis technology for concrete material text was established to extract key information from concrete material text. Based on actual concrete material text, the accuracy of extracting keywords using this method is 86.67%, which is superior to other commonly used keyword extraction models. Research findings provide a new method for processing non editable text data of concrete materials, which helps to improve the intelligent management level of concrete dam material data.

Construction scheme is one of the most important contents of construction organization design. The application of natural language processing to extract and review construction schemes from unstructured texts can improve review efficiency, enhance preparation quality, and identify potential safety and quality risks for early construction warnings. To extract construction schemes from unstructured texts, it is necessary to first clarify the content composition of different types of construction schemes and classify the contents of relevant paragraphs. Aiming at the classification of unstructured construction scheme paragraphs, classification of construction organization design paragraphs of urban pipe network engineering was taken as samples on the basis of in-depth study of construction scheme categories and content composition framework, and proposes a paragraph text classification model integrating Albert and TextRCNN. This model uses Albert pretraining language model for word embedding, and input the generated word vector into TextRCNN classifier to complete text classification. It outperforms Albert-TextCNN, which has the best classification effect among the other three models, and the accuracy increases by 0.79%. The experiment shows that: TextRCNN combined with Albert can effectively classify the contents of the construction organization design paragraphs, providing a basis for further construction scheme extraction.

Mega projects generate a vast amount of safety hazard inspection records, which contain valuable knowledge on the relationships between various hazard elements and are essential for safety management. However, manually extracting safety hazard information and uncovering their internal correlations is time-consuming and inefficient, making it difficult to provide timely feedback for on-site safety management. An intelligent extraction and knowledge mining method was proposed for hazard source entities based on the Universal Information Extraction(UIE) framework and an improved Apriori algorithm. First, a safety hazard entity recognition model is constructed using the UIE framework, with specific entity extraction prompts defined. The model is fine-tuned with few-shot learning to achieve efficient and accurate automatic extraction of safety hazard entities. Then, an improved Apriori algorithm is introduced, considering the constraints of hazard data types, to perform multi-factor association rule mining and visualization. Case analysis shows that the proposed safety hazard entity extraction model achieved F1 scores of 0.892 and 0.886 on the validation and test datasets respectively, significantly outperforming the baseline model′s scores of 0.253 and 0.307, and the overall entity recognition rate improves 36.66%. Additionally, the extracted multi-factor strong association rules are visualized using Sankey diagrams and association network graphs, demonstrating good interpretability. Research findings provides an efficient and intelligent method for mining knowledge from the vast amount of safety hazard text data generated in mega construction projects, offering data-driven support for the development of targeted safety management measures on construction sites.

The generator floor of a pumped storage power station, as an important component of the underground powerhouse, is a crucial site for power production. During the operation of the units, significant vibrations occur, which impose higher requirements on the decoration materials and construction techniques. Compared with the traditional decoration style of the generator floor in underground powerhouses, the Qingyuan Pumped Storage Power Station underground powerhouse innovatively adopts an exposed structural column decoration form to showcase the clear concrete process and industrial factory style. It uses galvanized keels in combination with aluminum single plates, and fills rock wool color steel plates to form a composite aluminum plate to replace the traditional infill wall. Moreover, an aluminum plate installation mobile construction platform is designed and fabricated. Through SOLIDWORKS finite element simulation analysis and BIM modeling to integrate related specialties, the entire construction process is guided and dynamically controlled, effectively ensuring the quality and progress of the generator floor decoration.

Starting from theoretical basis and engineering practice, this article derives a calculation formula for the reactance percentage of current limiting reactors that is in line with engineering practice, intuitive and easy to understand, and convenient to use. Taking the Qingyuan Pumped Storage Power Station as an example, the main process of selecting current limiting reactors was analyzed, and the main technical indicators of current limiting reactors were calculated. The selected parameters such as voltage drop and maximum temperature were verified to ensure that they meet the requirements of the specifications and practical engineering needs.

The good operation of ventilation system of water conservancy and hydropower project is very important for the safe operation of the project. ventilation control system is the basis for ensuring the orderly, stable and reliable operation of the entire ventilation air conditioning system. Its design mainly considers the system structure, networking mode, terminal control loop, linkage mode with other systems, etc. According to the different control areas, investment requirements, owners' requirements, design concepts and other factors of the building ventilation of water conservancy and hydropower projects, different design schemes can be selected. The classification design of selectivity for ventilation control system in water conservancy and hydropower projects under different engineering conditions was described, which is of great significance in improving design efficiency, structural stability, saving project costs and other aspects. At the same time, the ventilation control design scheme is summarized, which uses star Ethernet network, pure relay circuit and small PLC, and uses network linkage fire alarm to stop non fire fan. Its advanced design idea is practiced and verified in Qingyuan Pumped Storage Power Station. Finally, through years of design experience, the author also extended and discussed the future development trend and goals of ventilation control system.

The auxiliary control systems for hydraulic turbines and generators, the condenser dewatering system, and the spherical valve control system about Qingyuan Pumped Storage Power Station are decribede in this artical. It is also introduced the design of the guide vane opening, the rotational speed measurement, and the power supply principle for controlling circuit. Through these introduction and summary, it is easy to understand and master the control principles and the key issues of the automatic control system, which is closely to the daily operation of this power station. The result provide a basis and reference to the design of the upcoming pumped power stations.

In the power system of pumped storage power station, DC power supply, as the control power supply, relay protection and device power supply and the power supply of some important motors, is an important guarantee for the safe and stable operation of the whole unit. With the continuous advancement of smart grid technology, the protection and control loads within power stations are increasing, which further enhances the demand for automated and intelligent equipment. In DC systems, higher standards are set for overload protection and short-circuit protection of protective devices, requiring these devices to neither false operate nor refuse to operate, especially to avoid over-stepping actions. Once such a situation occurs, it may cause damage to power components, leading to an expansion of the accident scope, and even potentially triggering large-scale blackouts. The State Grid Corporation has initiated a series of research efforts regarding the reliability of DC power supplies, with a key task being the optimization of short-circuit level coordination for air switches in DC systems. The differential coordination of DC air switch is one of the main indicators to judge the reasonable configuration and safe operation of DC power supply system. The differential coordination calculation verifies whether the upper and lower air switches of DC power supply comply with the design specifications, and whether the fault removing range can be limited to the minimum to ensure the reliability of DC power supply to the greatest extent. This paper explains the basic principle and main method of range matching calculation in detail. Combined with the DC system level difference matching calculation of Qingyuan Pumped Storage Power Station, the paper puts forward the method and suggestions to optimize the DC power system configuration, eliminate the hidden dangers, and strengthen the operation and maintenance.

In the power system, for the needs of work and safety, it is often necessary to connect some parts of the power system and its electrical equipment with the earth, which is grounding. The ground network and soil of the Qingyuan pumped storage power station are modeled, the maximum grounding impedance of the power station is calculated and analyzed, and measures to reduce the grounding resistance are proposed.

The numerical simulation study of the exhaust air system mainly simulates the temperature field and velocity field of the airflow under the three working conditions of summer, transition season and winter for the exhaust flat tunnel and exhaust shaft, and establishes the equal scale numerical model through CFD calculation software to simulate the airflow organization and flow conditions of the exhaust system under different working conditions in the actual operation process. The CFD simulation method can be seen as basically simulating the flow of a fluid under the control of the flow equations(mass equation, momentum equation, energy equation). Through simulation, the distribution of basic physical quantities(such as velocity, temperature, humidity, etc.) at each location in the flow field of complex problems can be obtained over time. The numerical simulation study of the exhaust system mainly verifies the feasibility of the ventilation scheme of the exhaust system under the condition of designing the air supply and exhaust parameters and the layout of the air outlet, and provides reference opinions for the design to further optimize and improve the exhaust system scheme and equipment selection.

The operation condition of the reservoir of pumped-storage hydroelectricity is different from conventional hydropower station reservoir, which has the characteristics of frequent rise and fall of reservoir water level, fast rise and fall, and large drop depth. In order to adapt to the low-temperature operating environment in severe cold areas, higher requirements have been put forward for the construction materials and water stop system of the face slab rockfill dam in the design. Relying on Qingyuan Pumped-storage hydroelectricity, this paper systematically studies the cushion material design of concrete face rockfill dam, concrete mix ratio of face slab structure, surface water stop structure type, anti ice uplift measures of face slab surface, and puts forward suggestions on key anti freezing technologies of face slab rockfill dam in severe cold areas for reference of subsequent projects.

The Qingyuan Pumped Storage Power Station is equipped with a tail water emergency gate in the tailrace tunnel. The emergency gate slot is a square steel lining structure, and the lining plate material is stainless steel composite plate(Q355B+06Cr19Ni10), with a thickness of 30 mm. The base layer thickness is 26 mm, and the stainless steel composite layer thickness is 4 mm. The outer structure of the lining plate is made of ordinary low alloy steel and carbon steel materials. The upstream and downstream of the gate slot are square interfaces, connected to the steel lining of the draft tube by welding, and the rest are closed structures. The operation mode of the tail water emergency gate is dynamic closing and static opening. The water retaining head of the gate is 128 m, and the water closing head of the dynamic water is 114 m. Based on the structural characteristics of the gate slot, a welding process plan has been developed, and the design of the composite plate welding joint for the gate slot has been improved. An improved welding process has been proposed for the elevation weld seam of the gate slot. The quality of the connecting weld seam of the gate slot lining plate meets the Class I weld seam requirements specified in the design, and the welding quality is good.

This article takes the greening construction project of Qingyuan Pumped Storage Power Station as a case study, analyzes its characteristics, outlines the greening measures of the project, summarizes the experience and lessons learned during the implementation of the greening project, and puts forward relevant suggestions and thoughts.

This article analyzes the mechanism of ferromagnetic resonance in 500 kV GIS electromagnetic voltage transformers, the conditions required for resonance to occur, the determination method of resonance type, and the main countermeasures. Based on the excitation characteristics of traditional 500 kV GIS electromagnetic voltage transformers and the excitation characteristics of 500 kV GIS low magnetic density voltage transformers at Qingyuan Pumped Storage Power Station, as well as the circuit characteristics of voltage transformers and their connecting short busbars, high-voltage cables, and overhead lines under various operating conditions such as power station testing, commissioning, and maintenance, the equivalent capacitive reactance of independent systems and the excitation reactance of electromagnetic voltage transformers under typical operating conditions were calculated. Based on the PETERSON curve, the possibility of resonance generated by traditional transformers was analyzed, and the types of ferromagnetic resonance were quantitatively calculated and analyzed. During the contract execution phase, a study was conducted with the equipment manufacturer on the low magnetic density voltage transformer. The calculation result showed that the low magnetic density voltage transformer has outstanding anti saturation ability and will not experience ferromagnetic resonance under all predictable operating conditions.

The 10kV plant power system of pumped-storage power station in China has been operating with neutral point ungrounded for a long time. With the continuous increase of the capacity of plant power equipment, the cabling rate continues to rise. After single-phase grounding fault occurs, the arc often fails to self-quench due to the fault capacitor current being too large, and the single-phase grounding fault is often upgraded to an inter-phase short circuit accident. This paper studies the principle of three main grounding method: neutral ungrounded, neutral grounding through arc suppression coil and neutral grounding through little resistance, analyzes and compares the advantages and disadvantages of each grounding method, and studies the neutral grounding method which is most suitable for the operation of the power station in combination with the design principle of power consumption in Qingyuan Pumped Storage Power Station and the actual parameters of each equipment.

In order to more scientifically identify the characteristics and evolution rules of urban rainstorm under changing environment, and enhance the prevention and decision-making ability of urban response against flood disasters, daily precipitation data of Kunming National Reference Meteorological Station in 72 years(1951—2022) were used to study the evolution characteristics of rainstorm duration in Kunming during recent 70 years. Mann-Kendall test was used to analyze the variation trend and significance degree of precipitation, rainstorm amount, rainstorm days, rainstorm intensity in Kunming. At the same time, a variety of mathematical statistics method were used to verify the research conclusion. The result showed that in the past 70 years, the precipitation in Kunming had slightly decreased, the rainstorm volume had increased, the rainstorm days had increased, and the rainstorm intensity had increased. Light, moderate and heavy rain decreased, while rainstorm gradually increased. It was predicted that rainstorm would continue to increase and strengthen with the growth rate of 8.28 mm per decade in the future.

Copula function is used to model, and five kinds of edge functions commonly used in hydrology are used to fit the edge distribution of the inflow runoff of three important reservoirs in Menghai Irrigation area at different time scales. The Copula function is used to construct the optimal edge distribution of the three reservoirs at different time scales. The optimal Copula function is used to solve the probability of the inflow runoff of the two reservoirs at different time scales. Finally, the runoff calculated by the minimum monthly average flow method is evaluated by the Tennant method and used as the standard for reservoir water transfer in the irrigation area. It is mainly concluded that the best Copula function of the three reservoirs at the same time scale is Clayton Copula function. Under the same time scale, the probability of abundance and dryness synchronization is greater than the probability of abundance and dryness asynchronous in the combination of abundance and dryness encounter probability of three reservoirs. In all the probability combinations of wet and dry encounters, the probability of the three reservoirs being dry in all time scales is the largest, indicating that the three reservoirs in the irrigation area are the most likely to be dry years in the combination of wet and dry encounters. The runoff of the three reservoirs calculated by the minimum monthly average flow method in the non-flood season and the flood season basically meets the ecological needs in the Tennant method evaluation criteria, and the result can be used as the standard for reservoir water transfer in irrigation areas. Under this standard, Manman Reservoir can't supply a large amount of water to the irrigation area in December of last year and January of 2010, and can only supply water to the irrigation area through Mangui and Nadameng Reservoirs. In the non-flood season of 2011, the three reservoirs can be dispatched to the irrigation area. In July and August of the flood season in 2010 and 2011, the three reservoirs were all wet and abundant, and a large amount of water supply could be dispatched to the irrigation area. Except for July and August in 2010 and 2011, the three reservoirs are all dry encounters. Under the condition of satisfying the river ecosystem of the inflow river, the three reservoirs can properly regulate the water supply in the irrigation area. The research result can provide reference for water diversion of water supply reservoirs in Menghai Irrigation area.

The basin water security is related to food security, people's health, and social stability. To explore the historical evolution law of basin water cycle under the background of global warming and socio-economic development, a set of spatial-temporal characteristic analysis method for basin water cycle changes based on numerical simulation is established, which is of great significance for formulating relevant policies to adapt to and mitigate future possible water disasters. Taking the Chao Phraya River Basin in Thailand as an example, a high-resolution distributed hydrological model GBHM is constructed by comprehensively applying measured meteorological, hydrological and underlying surface data. The hydrological process of the Chao Phraya River Basin from 1985 to 2014 is numerically simulated, the spatial-temporal evolution law of water cycle elements and vegetation is analyzed, and the “double peak” characteristic of annual rainfall distribution is clarified based on the EOF method. The result show that the spatial distribution of precipitation in the Chao Phraya River Basin is uneven, concentrated in the northeast and southeast regions; over the past 30 years, the average annual rainfall in the whole basin and the four sub-basins of the upper reaches, including the Bang River, Wang River, Yong River and Nan River, has shown a significant upward trend, with the increase rates being 1.25 mm/a, 1.06 mm/a, 1.50 mm/a, 2.61 mm/a and 0.65 mm/a respectively; the annual precipitation distribution in the basin shows a double-peak pattern, of which the first peak appearing from March to May is mainly affected by the South Asian monsoon, and the second peak appearing from July to September is mainly affected by the Northwest Pacific monsoon and tropical cyclones; over the past 30 years, the annual runoff of the Chao Phraya River Basin and the four sub-basins in the upper reaches has shown a significant upward trend, with the increase rates being 284 million m³/a, 62 million m³/a, 29 million m³/a, 78 million m³/a and 104 million m³/a respectively. The result indicate that the South Asian monsoon dominates the early rainfall peak in the basin, while the Northwest Pacific monsoon and tropical cyclones dominate the late rainfall peak; the significant enhancement of the South Asian monsoon and tropical cyclones during the rainy season causes an increase in heavy rain, which in turn leads to intensified floods. Through the analysis of the spatial-temporal characteristic changes of various elements in the basin water cycle process, the unique role of the numerical simulation-based spatial-temporal characteristic analysis method in the analysis of basin water cycle elements is fully demonstrated, which can provide analytical tools and useful references for the formulation of basin water security policies.

Drought is a complicated extreme climate phenomenon, which has caused serious losses to agricultural production, economic development, water resources management and ecological environment in various countries and regions. The Ziya River Basin has been seriously affected by climate change and human activities for a long time, and the frequency and scope of drought events in the basin have shown an increasing trend in recent years. At present, satellite-based precipitation quantitative estimation shows great potential in drought monitoring, and in-depth research on the meteorological drought identification ability of different types of satellite products in the basin has important scientific significance for future drought warning, water resource allocation and agricultural production in the Ziya River Basin. The spatio-temporal accuracy, error and accuracy of monthly rainfall data of IMERG-F and SM2RAIN-ASCAT in Ziya River Basin were systematically evaluated based on three meteorological drought indices(SPI, SPEI and CI). Drought monitoring ability and drought event identification ability of satellite precipitation products on multiple time scales and spatial scales were evaluated comprehensively. The difference of drought grade spatial distribution and spatial efficiency index among satellite precipitation products was compared with typical drought events. The result show that: IMERG-F showed good performance in drought index estimation and drought event identification(R²>0.821, RMSE<0.448, POD>0.814, FAR<0.187). The drought effectiveness of SM2RAIN-ASCAT was poor(R²>0.081, RMSE<1.2, POD>0.442, FAR<0.571). IMERG-F and GAUGE show similar spatial drought patterns(0.507<spaef<="" p=""> </spaef

In order to study the quantitative relationship between drought loss of affected population and drought intensity and duration in Inner Mongolia. Based on the survey data and the Comprehensive Drought Index(CDI), the sample data of the affected population was obtained in Inner Mongolia. Based on the characteristic factors of drought intensity and duration, the correlation between the affected population and drought intensity and duration was analyzed, and the drought evaluation method and 3D model based on the 3D characteristic variables of drought intensity-duration-loss were constructed. The result showed that the affected population was determined by drought intensity, duration and other characteristic factors. The affected population was significantly correlated with drought intensity and duration, drought intensity and duration also have significant interaction. And the response relationship between the affected population and drought intensity and duration tended to be nonlinear.

The Xiong'an New Area is located in the central part of the North China Plain, which is characterized as one of the regions in China with relatively scarce water resources. The evolution of its drought characteristics is deemed significant for the economic and social development of the Xiong'an New Area and effective water resource management. Long-term meteorological monitoring data from 31 weather stations from 1975 to 2018 and CanESM2 climate model data were utilized to calculate the Standardized Precipitation Index(SPI) across various time scales. Additionally, different types of Copula functions were employed to construct a two-dimensional joint probability distribution model based on the characterization of drought features. The aim was to analyze the drought evolution patterns and risk status in the secondary water resource zone where the Xiong'an New Area is located under the influence of climate change. At both monthly and seasonal scales, a spatial redistribution of the frequencies of mild, moderate, and severe droughts has been observed in the secondary water resource zone, although the overall changes remain minimal. In contrast, a significant increase in the frequency of extreme drought events has been recorded. On the annual scale, while a decrease in the frequency of moderate droughts has been noted, significant increases in the frequencies of mild, severe, and extreme droughts have been observed, along with notable shifts in their spatial distribution characteristics. The Clayton Copula function was found to provide the best fit for drought duration and intensity in the region. The univariate return periods for these variables are situated between the joint return period and the co-occurrence return period; as the return period extends to 100 years, a drought duration of 6.9 months and a drought intensity value of 7.4 have been reached, while the co-occurrence return period exceeds 200 years. The results indicate that a marked clustering of mild, severe, and extreme drought events is expected to occur in the Xiong'an New Area and its surrounding regions. This suggests an increased potential risk to the water resource carrying capacity in the future, while the probability of prolonged high-intensity drought events remains relatively low.

The construction of digital twin watersheds is the most distinctive feature of smart water conservancy. The model platform provides algorithmic support for the construction of digital twin watersheds, and the efficient model instantiation is a critical technical bottleneck that urgently needs to be addressed in the practical application. Focusing on the demand for dynamic online calibration during model instantiation, it introduce the SPOTPY toolkit and select the widely used Xin'anjiang model in China as the case study. In accordance with the generalized model construction specifications set by the Ministry of Water Resources and the Huai River Commission, the example module provided by the toolkit was modified based on the SCEUA optimization algorithm. Model parameters, optimization method parameters, objective functions, rainfall datum, etc., were transformed into method input variables. Additionally, technologies were utilized such as FastAPI and Docker for microservice construction and containerization to build a dynamic calibration microservice instance for watershed hydrological models. The practical application of this technology in the construction of the digital twin Huai River model platform demonstrates that this method is efficient, mature, and reliable, providing important technical references for the implementation of online dynamic calibration of model instantiation.

The initial allocation of water rights is the premise and basis for promoting the reform of water rights. At present, the ownership of water rights is not clear, and the rights and obligations are not clear, which makes it difficult to cultivate the water market and carry out the water rights trading effectively. Based on the AHP method of fuzzy optimization theory, an improved water rights allocation model is proposed. By integrating multiple factors and using advanced decision analysis tools, it provides a more accurate, fair and efficient water resources allocation solution, improves the scientific nature and adaptability of water rights allocation, and better meets the complex needs of modern society for resource management. Taking Ding'an River basin as an example, the model is applied to explore a new way of initial water rights allocation scheme, which has certain exploration value for realizing efficient and optimal allocation of water resources in the basin.

Nanhaizi flood detention basin is an important component of North Canal basin flood control system. To provide support for its optimal operation, the current storage capacity of Nanhaizi flood detention basin was analyzed firstly based on Arcmap, and a two-dimensional hydrodynamic model was established based on HEC-RAS. The results showed that the current storage capacity of Nanhaizi flood detention basin was 2 300 000 m³, which was 300 000 m³ less than the planned storage capacity of 2 600 000 m³ in 50 years. Taking the elk park as a part of the flood detention basin can solve this problem optimally, and it was determined that the new regulating gate was opened when the water surface elevation of the lake reaches 29.75 m, while closed when the water surface elevation of the elk park reaches 29.75 m. In order to ensure the stability of the project, the width of the new connecting channel and regulating gate was determined to be 5 m according to the simulation result. Compared with the curve of water surface elevation to storage, the two-dimensional hydrodynamic model based on HEC-RAS can consider the flow direction and head loss of the water and simulate the actual flow better according to the result.

The study of flood simulation and forecasting for small and medium-sized rivers with insufficient data is a key and difficult problem in hydrological forecasting research. Paitan River Basin in Guangzhou was taken as the target basin, and the synthetic unit hydrograph method and the hydrological similarity parameter transplantation method were applied for hydrological simulation and forecasting research. In the hydrological similarity parameter transplantation method, the Xifu River Basin is used as the reference basin. Based on the terrain index frequency analysis result of the Xifu River and Paitan River basins, it is considered that the two basins have hydrological similarity. The Xinanjiang model parameters of the reference basin are directly transplanted to the target basin for typical flood simulation and forecasting. The flood simulation result of the above two method in the target basin are compared and analyzed with the measured flood data. The result show that the parameter transplantation method based on the Xinanjiang model requires more hydrological and geographical data from the reference basin and the target basin, and has higher overall forecasting accuracy than the synthetic unit hydrograph method. The synthetic unit hydrograph method requires less hydrological and geographical data and has lower overall accuracy, but as the flood magnitude increases, the forecasting accuracy will significantly improve. Based on the applicability conditions and application effects of the above two method, a flood forecasting method for small and medium-sized rivers with insufficient data is proposed.

The engineering technology and construction challenges of the 305-meter-level ultra-large hydropower station are beyond imagination, with many technical indicators surpassing current regulatory requirements. Mastering the deformation laws and formulating deformation monitoring indicators are extremely complex task. Firstly, the significant deformation characteristics of the active dam body are analyzed and summarized from multiple perspectives based on 1∶1 prototype test parameters, providing feedback on the actual service performance of the dam body and exploring external influencing factors and laws. Secondly, by integrating load sets and load effect sets, various influencing factors are comprehensively determined through deterministic functions and physical inference method. Based on measured data, the coefficients of each factor in the model are determined, allowing the calculation of the load effect set for a certain set of load sets. Subsequently, a deformation monitoring statistical model for super high arch dams is established to determine the working status of buildings and monitor them. Through deformation prediction analysis of typical measurement points, the result are compared and analyzed with other method, leading to the derivation of deformation monitoring indicators and optimal formulation method for super high arch dams. Thirdly, a three-dimensional nonlinear finite element model of the dam body is established, and an incremental step difference algorithm is proposed, considering the self-weight of the dam body and external water load, which accurately simulated the actual deformation behavior of the arch dam. The research result provide a strong reference for the exploration and analysis of similar projects in the future.

The operating head of the 1~# spillway tunnel is as high as 83 m, with a maximum average flow velocity of over 35 m/s. Adopting a single slope with a bottom slope gradient of 0.81%. Three aerating facilities are designed with a combination of ridges and grooves. In order to verify the rationality of the design scheme of the aeration facility. Optimization research was conducted on the shape of the aeration facility through normal hydraulic model test with a scale of 1∶40. The result show that there is a significant negative pressure on the side wall of the diffusion section, with a negative pressure value of-86.6 kPa, and cavitation water flow is prone to occur at high speed water flow. The aeration facility has severe backflow in the cavity, intermittent blockage of the ventilation holes, small ventilation well area, and a maximum air-water flow ratio of 1.8%. The ratio of the 3~# aeration facility is only 0.6%. After experimental research, it is proposed to cancel the diffusion section, move the 1~# aeration facility forward and adjust its shape to a differential sudden expansion and drop form, and adjust the 2~# and 3~# aeration facilities to a differential form, and a steeper downstream bottom slope. The result show that the optimized body shape can meet the requirements of aeration, with an air-water flow ratio of over 4.2% at the flood control water level and over 7.0% above the normal high water level. The aeration effect is good, and it has important reference value for solving the aeration design of small bottom slopes in tunnels.

The dam site of Beikeng Reservoir is asymmetric wide valley terrain, the lithology is tuff, the rock is hard, and the overburden on the left bank is relatively deep. Compared with the gravity dam, the local material dam has strong adaptability to topographic and geological conditions, better material source conditions and less investment. Considering that the construction period of the weathered material core wall rockfill dam is long, and it has certain interference with the adjacent spillway, the recommended dam type is the face rockfill dam. Aiming at the problem of deep overburden layer of dam foundation, considering the scheme of ‘retaining part of the overburden layer + vibroflotation gravel pile', the risk of deformation and cracking of the dam panel is relatively large, the construction is difficult, the construction period is long, and the project investment is large. Therefore, the dam foundation adopts the treatment scheme of ‘all excavation of the overburden layer'.

When the local cracks appear in the anti-seepage face of asphalt concrete face rockfill dam, it will have a great impact on the safety of the dam. In order to understand the influence of local failure of asphalt concrete panel on the seepage of dam body, the asphalt concrete panel rockfill dam in the upper reservoir of a pumping and storage power station in Gansu province were taken as the example, and establishes a three-dimensional finite element model to calculate the seepage field of the dam body when the panel fails locally, and analyzes the influence of local cracks in different parts of the panel and different crack sizes on the seepage field. The result show that the influence of local failure cracks on the seepage field of the dam is mainly concentrated in the vicinity of the cracks. With the increasing of the crack width, the flow through the dam foundation rock mass increases successively, and the seepage slope of the dam foundation rock mass decreases, and the seepage slope of the dam foundation rock mass is basically unchanged. The saturation zone is formed in the small area inside the cushion around the crack of the panel, and the influence of the local failure of the panel on the seepage field does not exceed the cushion zone. The saturation zone and the infiltration flow under the crack are large, so it is extremely important to ensure the gradation and impermeability of the cushion material. At the same time, it is found that the influence of local failure on the seepage field of asphalt concrete panel is related to the failure location and crack width, and the failure location has greater influence on the seepage field than the failure seam width. The result can provide reference for similar engineering design and construction.

In response to the challenges faced by settlement prediction models for earth-rock dams, such as the susceptibility of regression models to multicollinearity, and issues like overfitting, local minima traps, and difficulty in determining hyperparameters in neural network models, an optimized model was proposed based on Empirical Mode Decomposition(EMD) and Long Short-Term Memory(LSTM) neural networks. Firstly, EMD is employed to perform multi-scale decomposition of time series data from Global Navigation Satellite System(GNSS) measurement points, extracting trend and periodic components. Then, Principal Component Analysis(PCA) is utilized to select key influencing factors, reducing data dimensionality and enhancing the generalization capability of the model. Finally, an LSTM is used to construct the time series model, and the Whale Optimization Algorithm(WOA) is applied to optimize the hyperparameters of the LSTM, improving the model′s prediction accuracy and convergence speed. The experimental result show that this model offers significant advantages in the settlement prediction of earth-rock dams, with a Mean Squared Error(MSE) of 7.070 1, a Mean Absolute Error(MAE) of 1.885 9, and a coefficient of determination(R²) of 99.83%. Compared to traditional method, this model demonstrates notable improvements in noise reduction, feature capture, and hyperparameter optimization, providing an accurate and reliable solution for settlement prediction in earth-rock dams.

The meteorological environment in the high cold and high altitude area is complicated, and there are great differences between the design conditions and the actual conditions, which may increase the cracking risk of concrete under certain conditions. Therefore, it is necessary to conduct inverse analysis of the thermodynamic parameters and temperature field during the construction period, and optimize the temperature control measures to ensure the construction safety and quality. The whole process simulation analysis method of the dam and the measured temperature data during the construction period are used to comprehensively compare and analyze the differences between the indoor thermal and mechanical parameters and the actual parameters on site. By using the inversion temperature parameters and the actual pouring progress, the temperature control measures of the steep slope dam section are optimized by simulation analysis. The inversion analysis showed that the calculated value was in agreement with the measured value after the adiabatic temperature appreciation was adjusted to 27.5 ℃. When the final value of adiabatic temperature rise of secondary normal concrete is 35 ℃, the calculated value is the closest to the inverse analysis value. The comparison between design adiabatic temperature rise and inversion analysis shows that the early temperature of inversion is higher than the design value, but the final value is lower than the design value. The simulation result show that the maximum stress along river is 1.50 MPa and the safety factor is 1.64. The stress and safety factor in other areas are within the reasonable range, but the safety reserve of foundation strong confinement area and normal concrete bedding is slightly lower. On the basis of accurate inversion of thermodynamic parameters, combined with the result of simulation analysis, it is found that the temperature control measures of the foundation strongly confined area and the normal concrete bedding need to be further optimized, especially the maximum temperature should be further strictly controlled and the surface protection should be strengthened. The inversion of parameters and the feedback method of temperature stress field used in this paper can reflect the actual construction situation more accurately, and provide more reliable technical support for the optimization of construction standards and measures of mass concrete.

A nonlinear seismic damage analysis method for the sluice foundation water system had been established to address the shortcomings in the seismic analysis of reinforced concrete sluice structures. Taking a flood control gate project in a certain VIII degree area as an example, the dynamic response, damage range and degree of the water gate structure under earthquake action were studied. Based on the calculation result, the nonlinear earthquake damage and failure mechanism of the water gate foundation water system was revealed. The result showed that:(1) The method considered factors such as wireless foundation radiation damping effect, concrete dynamic damage, reinforced concrete bonding and sliding effect, and fluid solid coupling effect between water body and water gate structure, which could accurately reflect the stress state of reinforced concrete sluice under earthquake action. The accuracy of the established method was verified by comparing the calculation result with other method;(2) Under earthquake action, concrete damage occurred at the connection between the bent column and the gate pier, and the damage area basically covered the cross-section of the bent column, with the maximum damage value reaching 0.659. The concrete was basically in a state of damage and failure;(3) As the duration of the earthquake increased, concrete damage began to appear at the corner of the bent column, and the damage value and area continued to increase. When the damage area run through the entire cross-section of the bent column, it could be considered that the chamber structure had been undergone seismic damage.

Based on the construction of V-shaped rigid pier of cross-railway viaduct, the temperature control measures of high-strength special-shaped mass concrete were studied. The finite element models of the pier and the two sections of the inclined leg were established respectively. The characteristics of the temperature peak with age and the internal temperature field under different cooling measures were analyzed. The result of temperature monitoring and simulation were compared. The result show that the key parameters of temperature control are different in different sections. The peak temperature of the pier is the maximum temperature difference between the surface and the inside of the inclined leg, which is the peak temperature for pier and the maximum temperature difference between surface and inside for inclined leg. The crack resistance of high strength mass concrete is improved, the peak temperature and the maximum temperature difference between the surface and the inside are increased by 5 ℃ compared with the existing specifications, and the temperature difference between the surface and the atmosphere can be increased by 10 ℃.

There is a significant discrepancy between the actual and designed unit consumption in curtain grouting construction for water conservancy and hydropower projects, with an observable trend of increasing consumption. The causes of this increase are multifaceted, complex, and variable, primarily influenced by grouting materials, human factors, grouting pressure, and the lithology of the formation being irrigated. However, effective measures can be implemented to control this issue. Over the years, during the revision process of relevant specifications, emphasis has been placed on addressing this concern. Each revision has progressively refined parameters affecting unit consumption, aligning them more closely with actual engineering practices and enhancing operability and implementation. The factors contributing to the significant difference in unit consumption are influencing its increase in curtain grouting. By employing effective control measures and treatment strategies, the designed unit consumption can be made consistent with the actual construction unit consumption, thereby preventing design changes due to increased material costs. The research findings provide valuable reference for similar projects encountering comparable situations.

In order to ensure the progress of dam pouring and the quality of dam foundation consolidation grouting, it is necessary to conduct dam foundation consolidation grouting test. According to the geological conditions of the test area, the consolidation grouting test scheme is established, and the wave velocity, lifting deformation and water permeability of the rock mass before and after grouting are analyzed and discussed. The average wave velocity of rock mass after grouting is 7.5% higher than that before grouting. In the experiment, no lifting signs of concrete deformation were found in each hole section. The average water permeability before and after irrigation was 31.92 Lu and 12.96 Lu, respectively, and the water permeability decreased significantly after irrigation. These result show that the consolidation grouting has a good effect.

A large underground cavern project is located in a severely cold area, with a winter period of 208 days, an average temperature of-19.7 ℃, and a minimum temperature of-45.4 ℃. The distribution of this cavern is complex and intricate, with a long construction period for the main cavern and multiple intersections of construction tunnels and water curtain tunnels. With the progress of construction, the connection mode, ventilation channels, ventilation distance, and ventilation circuit between tunnels are constantly changing. In response to the difficulties encountered during the construction process mentioned above, we adopted the Computational Fluid Dynamics(CFD) theoretical model to simulate the airflow and temperature fields of the water sealed cavern during different construction periods. We corrected the simulation result through on-site data collection, striving to guide the construction through computational simulation. We have utilized the result of computational simulation to optimize and adjust the ventilation and heating layout during winter construction, ensuring that the ambient temperature inside the tunnel remains above 5 ℃ under extreme cold conditions. At the same time, we have fully utilized the residual heat of the gas discharged from the tunnel to solve the problem of road icing in the traffic tunnel, providing a good guarantee for the advancement of engineering construction.

Taking the left line of the section from Yunxi Park Station to Xiaojinzhong Station on Guangzhou Metro Line 12 as an example, the impact of large-diameter shield under-passing on the settlement and deformation of the existing municipal tunnel under complex geological conditions of upper soft and lower hard layers was investigated. By adopting protection measures and technical solutions at different stages, guidance was provided for the design and construction of the large-diameter shield under-passing. Based on the theoretical analysis, through the comparison and demonstration of the protection design scheme of Jinyuan Road Tunnel, the scheme of setting concrete box culvert at the deformation joint is finally determined. Based on the theoretical analysis, through the comparison and demonstration of the protection design scheme of Jinyuan Road Tunnel, the project adopted the scheme of setting concrete box culverts at the deformation joint. During the process of under-passing, measures such as excavation control, radial hole grouting, deep borehole grouting behind the segment, and increased monitoring frequency were taken, effectively solving the technical difficulties of settlement deformation control and providing reference for similar projects.

Cement mixing piles are widely used in many soft soil areas in China to treat weak foundations. However, in view of its hidden engineering characteristics, how to evaluate its post-construction quality in a timely and effective manner is still a lack of scientific and effective method. Taking a soft foundation mixing pile treatment project in Zhongshan City, Guangdong Province as an example, it is based on the intelligent monitoring system combined with the field tests. It uses the AHP-fuzzy comprehensive evaluation method to evaluate the quality of cement mixing piles. Firstly, the evaluation index and membership function of the quality of the mixing pile are determined, and then the weight of the corresponding evaluation index is calculated by the analytic hierarchy process. Secondly, the fuzzy comprehensive evaluation method is used to evaluate the quality of the cement mixing pile. Finally, the evaluation result are compared with the engineering practice. The result show that the error between the monitored pile length and the actual pile length is less than 2%. The goodness of fit between the ash content of the monitoring section and the strength of the pile body is high, and the goodness of fit between the average speed of the drill pipe and the integrity of the pile body is also high. The fuzzy comprehensive evaluation result of pile quality are in good agreement with the core sample characteristics of the core sample. The result show that the application of this evaluation index system combined with the fuzzy comprehensive evaluation method can well reflect the result of the quality inspection of cement mixing piles in practical engineering, and verify the feasibility of this method for the rapid evaluation of the quality of cement mixing piles. It provides a reference for improving the content of the construction stage of cement mixing piles and improving the construction quality.

The construction of pumped storage projects involves the construction of underground caverns such as underground powerhouses and diversion tunnels, with tight construction schedules and high quality requirements. In order to improve the digital level of tunnel engineering construction, increase construction efficiency, and ensure project quality, a digital system for tunnel construction based on microservice architecture has been constructed, and lightweight and visualization of large-scale 3D point cloud data for tunnel construction have been achieved based on Cesium. The system utilizes point cloud data collected by 3D laser scanners during tunnel excavation, support, and lining stages, combined with tunnel design parameters, to achieve statistical analysis of quality factors such as tunnel over and under excavation, support deviation, shotcrete and lining thickness and flatness. Based on 3D point cloud data, the system monitors the progress of tunnel engineering, analyzes construction intensity, measures the quantities of tunnel excavation and support, and conducts 3D visualization queries on tunnel deformation. The system can automatically generate tunnel construction quality analysis reports based on analysis result and meet the requirements of engineering management for inspection and evaluation forms and visas. The system has been applied in the access tunnel of a pumped storage power station project, providing effective support for the construction management of the project.

The crisscross layout and parallel crossing excavation method of of underground caverns make it difficult to ventilate and disperse smoke, and the ventilation effect directly affects the construction progress and safety of the project. Taking a ground water-sealed cavern project as the research object, the OpenBuildings Designer modeling software is redeveloped by Addins method, and the BIM model of the groundwater-sealed cavern is parameterized. According to the initial conditions and boundary conditions consistent with the project, the standard turbulence model and the component transport model are used to simulate the distribution of the wind flow field and the migration of harmful gases in the cavern. The result show that the position of the cross section has a greater influence on the ventilation effect in the range of the secondary lining step distance than the distance from the outlet of the air duct to the working face. When the air duct outlet is located in the middle of the vault and 50 m away from the working face, the ventilation effect within the second lining step distance is the best, and only 9.7 min of ventilation time can meet the needs of long-term operation of construction personnel. The harmful gases in the tunnel are concentrated in the main channels such as connecting roadways and construction roadways. It is considered that jet fans can be arranged in an orderly interval in the main channel to improve its ventilation efficiency.

The stability of surrounding rock of underground cavern is related to the construction safety of underground engineering and the safe operation of underground buildings in the later stage. The stability of surrounding rock of an underground powerhouse in southwest China is evaluated based on the type check of surrounding rock in construction geology and the analysis of block stability. And through the comparison and analysis of the displacement monitoring data of surrounding rock during construction period and the result of FLAC^3D numerical simulation, the reinforcement effect of surrounding rock is evaluated. The evaluation results show that the surrounding rock of the underground powerhouse mainly consists of class Ⅱ and Ⅲ surrounding rock, accounting for 96%, and class Ⅳ only accounts for 4%. Moreover, due to timely reinforcement, large-scale block collapse of more than 10 m³ did not occur during construction, and the surrounding rock stability is generally good. The displacement of the top arch of the surrounding rock of the underground powerhouse is millimeter, and the reinforcement effect of the top arch surrounding rock is good. The displacement of side wall is in the order of cm, and the reinforcement effect of side wall surrounding rock is preferable good. Comparatively speaking, the reinforcement effect of the top arch is better than that of the side wall. The research results can be used as reference for similar projects.

Soft clay foundation is easy to produce uneven settlement, which threatens the safety of hydraulic structures. Clay consolidation grouting is an effective means to improve its mechanical properties, but the traditional finite element method and discrete element method have limitations in dealing with the splitting process of clay grouting. In order to investigate the cracking mechanism of clay grouting, a meshless numerical method was established to simulate the development process of soil grouting splitting veins, in the SPH framework, the “soil particles” and “slurry particles” are defined, and the interaction between “slurry particles” and “soil particles” under grouting pressure is deduced. A fracture marker κ, which can reflect the failure of particles, is introduced, which can simulate the progressive expansion of soil grouting splitting cracks. Considering the heterogeneous characteristics of soil, Weibull distribution function is introduced to consider the heterogeneous distribution of tensile strength, and the soil grouting splitting characteristics under different heterogeneous characteristics are numerically simulated. The result show that the improved SPH method can well simulate the development process of slurry veins during clay grouting splitting. The above implementation fully demonstrates that: When the soil heterogeneity is not considered, the extension shape of slurry veins is single and symmetrical, while when the soil heterogeneity is considered, the soil grouting fracturing shape is more complex, forming a criss-cross network of slurry veins. The soil disturbance caused by grouting is mainly concentrated in the vicinity of the grouting hole before the grouting pulse cracking, but after the grouting pulse cracking, the soil along the grouting pulse is greatly disturbed. Finally, the formation mechanism of soil grouting fracturing fracture is discussed. It is found that soil grouting fracturing bifurcation is caused by soil heterogeneous characteristics, and the application prospect of SPH in soil grouting fracturing simulation is prospected. Future research should focus on the development of 3D high-performance parallel SPH algorithm.

In order to study the change of compaction effect and horizontal stress along the depth of collapsibility loess highway subgrade treated by rammed-expanded lime-soil compaction piles with different pile diameters and pile spacing, the compaction coefficient, horizontal stress, over-consolidation ratio, cone tip resistance and side-wall resistance around the pile were analyzed. The results show that the compaction coefficient, collapsibility coefficient, horizontal stress, consolidation degree, cone tip resistance and side-wall resistance of soil between piles can be significantly increased in the range of treatment depth, and then the bearing capacity of the foundation is mentioned. When the pile spacing increases from 1.0 m to 1.2 m and 1.5 m, the average soil compaction coefficient between piles increases by 1.37% and 4.11%, and the average collapsibility coefficient increases by 1.75 and 2.79 times, respectively. When the pile spacing is 1.0 m, 1.2 m and 1.5 m, the average horizontal stress ratio corresponding to the 400 mm pile diameter is 3.23, 2.47 and 1.92, the over-consolidation ratio is 11.58, 6.64 and 3.94, respectively, the average cone tip resistance increases by 2.54 times, 1.92 times and 1.31 times, respectively, and the side-wall resistance increases 3.07 times, 2.35 times and 1.47 times, respectively. The average horizontal stress ratio corresponding to the pile diameter of 450 mm is 3.52, 2.74 and 2.21, the over-consolidation ratio is 13.80, 8.26 and 5.27, respectively, the average cone tip resistance increases by 2.77 times, 2.03 times and 1.39 times, and the side-wall resistance increases by 3.40 times, 2.59 times and 1.66 times, respectively. The influence of pile spacing on the soil parameters above is greater than that of pile diameter. In practical engineering, it is recommended to treat collapsible loess foundation with rammed-expanded lime-soil compaction pile with pile spacing≤1.2 m.

There are many factors that affect the groutability of rock mass, especially the accuracy of judging the groutability of rock mass with the empirical formula is low for the hidden rock mass fracture. Aiming at the above problems, the support vector machine method is used to establish the prediction model of rock mass groutability analysis in order to realize the fast and accurate analysis of rock mass groutability. Based on the analysis of the influencing factors and the small sample characteristics of the grouting data set, the regression prediction SVR model and classification prediction SVM model of rock mass groutability were established respectively. Further, by improving the gray Wolf optimization algorithm and enhancing the whale optimization algorithm, the penalty factor C and kernel function parameter g of the prediction model based on support vector machine are optimized. The result show that compared with other prediction models, the classification prediction accuracy of the groutability prediction model proposed in this paper is improved by about 6.5%, and it has the obvious advantage of fast convergence, which verifies the accuracy and effectiveness of the prediction model of rock mass groutability analysis based on support vector machine.

To enhance the accuracy of high-density electrical method, an innovative data processing technique has been proposed, which is implemented through time-shift processing during a single data acquisition, simplifying the complexities of traditional method. Numerical simulation of theoretical models was combined with practical application cases to explore the effectiveness in karst detection.Results indicate that the method can effectively identify faults and low-resistivity anomalies within the resistivity variation profiles. In practical cases, inversion result show a high degree of correlation with borehole data, and the resistivity variation rate is significantly related to the permeability coefficients obtained from pumping tests. Additionally, the distribution characteristics of karst features are closely linked to the local minima in the resistivity variation profiles. This method successfully reveals the distribution of underground karst fractures in the Xiliu Creek reservoir area, providing essential scientific evidence and guidance for subsequent seepage curtain construction.It also provides a new solution for the refined exploration of karst in reservoir areas using high-density electric method.

The surface seepage problem has attracted attention during the operation period of Urban large underground water conveyance culvert. Taking the surface seepage of a large urban underground water conveyance culvert as the background, the numerical simulation analysis of surface seepage is carried out according to the engineering geological and hydrogeological conditions. Typical sections are selected to reflect the different leakage degrees of the culvert by setting different permeability coefficients of the lining, and then the influence on surface water seepage is analyzed. The result show that the more serious the leakage of the lining, the smaller the dissipation of the pore pressure of the lining, the more obvious the increase of the pore pressure of the soil at the top of the lining, and the increase of the surface pore pressure. When the permeability coefficient of the lining reaches 1 m/d, the surface water is exposed under long-term seepage. Compared with the field groundwater monitoring data, it is close to the simulation value. The research result have reference value for the design and operation of similar urban large underground water conveyance culvert.

Leakage is a frequent disease in earthen dykes. Transient electromagnetic method is expected to achieve high efficiency detection in the low resistance area of deep seepage in dykes. The finite element method is used to simulate the diffusion process of the transient electromagnetic field inside the dam, reveal the response law of the transient electromagnetic measurement curve to the low resistance area of leakage, quantify the change of the magnetic induction intensity of the channel with and without leakage, and finally carry out field tests combined with practical projects. The result show that the transient electromagnetic field diffuses ellipsoid inside the dam, and the magnetic field distribution is relatively concentrated and the magnetic induction intensity increases greatly in the low-resistance area of leakage during a specific time period, which presents a local convex shape and obvious volume effect on the multi-channel map. In the process of response, the magnetic induction intensity decreases logarithmically, and the response of the leakage area in the embankment can be highlighted by using the relative deviation value. Through field test and comparison of core drilling, the transient electromagnetic method can effectively detect the low resistance zone of leakage, and the multi-channel map of relative deviation value and apparent resistivity map can directly show the distribution of low resistance zone inside the dam.

Aimed to investigate the erosion distribution characteristics of dual pile foundations of mountainous road bridges under sand laden flow, a three-dimensional erosion numerical model of the dual pile foundation was established using Fluent. The DPM model was employed to simulate sediment particles, and the Finnie erosion prediction formula was combined to explore the erosion distribution characteristics of the dual pile foundation under different water flow velocities, sediment particle sizes, sediment concentration, pile wall roughness and arrangement type of double piles. The result show that the velocity distribution around the piles has a significant influence on the erosion distribution of the pile foundation. The erosion of the front pile is relatively sparse, mainly distributed on both sides of the water-facing surface, while the erosion distribution of the rear pile is more concentrated due to the influence of the wake zone of the front pile. With increasing water flow velocity, the overall trend of the maximum erosion rate of the pile foundation increases, but the rate of increase decreases after reaching a certain velocity. Moreover, as the sediment particle size, sediment concentration, and pile wall roughness increase, the maximum erosion rate of the pile foundation also increases. Specifically, for sediment particle size and pile wall roughness, when increased to a certain value, the rate of increase in the maximum erosion rate of the pile foundation decreases, while for sediment concentration, when increased to a certain value, the rate of increase in the maximum erosion rate of the pile foundation accelerates. With the increase of pile center distance, the maximum erosion rate of the front and rear piles of the tandem double pile increase, and the increase decreases gradually, while the maximum erosion rate of the left and right piles of the parallel double pile increase first and then decreases.

Deeply buried tunnels, even after adopting combined plugging and drainage treatment measures, still face difficulties in simultaneously meeting the dual control requirements of external water pressure and seepage flow standards. Exploring new seepage control method is of significant importance. To this end, the concept of “plugging, collecting, and draining” for seepage control is proposed, and the evolution laws of the surrounding water environment of the lining under different seepage control measures are analyzed. The research shows that grouting for water plugging plays a significant role in reducing the tunnel's seepage flow but is challenging to completely prevent leakage. After implementation, the tunnel exhibits the typical characteristics of “low flow, high water pressure”. Drainage and water collection have a noticeable pressure relief effect but cannot control the seepage flow, making the combined application of plugging, collecting, and draining the key to reducing flow and relieving pressure. When drainage measures are shallow, the pressure relief capability is poor, and when they are deep, the effectiveness of grouting for water plugging is weakened, limiting the pressure relief effect in water-rich and high-pressure strata. By setting up a collection layer, the seepage channels around the lining can be effectively dredged, which does not affect the grouting sealing and significantly improves the drainage and pressure relief effect. In cases of partial blockage of drainage holes or non-full-section drainage, the design of plugging, collecting, and draining can provide channels for local seepage and water pressure dissipation behind the lining, thus avoiding the lining bias effect. The new plugging, collecting, and draining measures can offer a new approach for the design of seepage control under high external water pressure in water-rich strata.

When excavating deep buried tunnels in complex and fractured formations, how to quickly and effectively solve common problems such as leakage and water inrush has become the focus of ensuring tunnel safety and effective excavation. The construction of a certain water conservancy tunnel was taken as the engineering background, measures the water inflow, water inflow points and other data, combined with long-distance directional drilling technology. Four grouting holes are arranged on a hole layout circle with the tunnel axis as the center and a radius of 7.02 meters. The horizontal section is parallel to the tunnel axis and the minimum distance from the tunnel contour line is 2.5 meters. Advance pre grouting is carried out through bidirectional directional long drilling on the ground. The result show that the permeability rate is not more than 3 Lu, and the water output of the tunnel excavation treatment section is not more than 147 m³/h. The treatment effect is obvious. From this, it can be concluded that compared with traditional ground vertical hole curtain grouting and palm face cyclic grouting processes, this grouting technology reduces the number of boreholes, improves grouting efficiency, controls grouting range, saves grouting materials and construction period, creates favorable conditions for safe tunnel excavation, and has certain reference significance for similar tunnel water blocking treatment.

The bottom plate of the left side of the spillway groove and nose section of the EP hydropower station was washed away during flood discharge, posing a threat to the safety of the dam operation.The hydraulic model test and on-site inspection revealed that the main reasons for the water damage to the bottom plate of the spillway discharge channel are: The unreasonable design of the aeration bucket position leads to high pulsating pressure on the bottom plate of the discharge channel and poor aeration effect; The shape of the flip bucket is unreasonable, and the flow back to the channel is not smooth, [Results]ing in a greater intensity of backflow in the downstream river channel; The flatness of the bottom plate of the spillway channel is poor, the water stop is ineffective, and there are defects in the quality of the concrete. In order to completely eliminate the safety hazards of spillway discharge, engineering treatment measures such as optimizing the layout of aeration facilities, adjusting the nose bucket to a large angle differential nose bucket, and dismantling and rebuilding the bottom plate of the spillway discharge channel have been proposed. Prototype observation experiments have shown good treatment effects, which can provide reference for the treatment of other spillway water damage hazards.

Pumping test in borehole should be conducted before dewatering of foundation excavation of water resources and hydropower engineering. Several wells were arranged at an inverted siphon of a deep and large foundation pit. Single well pumping test and double wells pumping test were conducted and permeability coefficients were calculated. Calculation formula of drawdown in the form of a logarithmic function was derived according to drawdown of single well pumping test. Water yield calculation formula of single well pumping test was derived according to Skabaranovic formula. The calculated value is relatively close to the actual value, which indicates the effectiveness of both formulas. Calculation formula of drawdown between both pumping wells in the form of a quadratic function was derived according to drawdown of single well pumping test, which can be used to determine the minimum drawdown during double wells pumping of foundation pit. The application of all calculation formulas can be the basis for the design of dewatering scheme of foundation pit.

The water gates and pump stations of traditional pump gate water conservancy hubs are usually nonintegrated, facing difficulties in occupying large waterway areas, inconvenient integrated intelligent control, and poor urban construction aesthetics. Therefore, the floating pump station at the mouth of Suzhou River was taken as an example and proposes a new type of integrated pump gate: a large-scale floating barrage pump station with a single-gate configuration. However, the lateral thrust power of the pump station and its impact on riverbed silt during operation are not yet clear. Therefore, this study calculates the hydrodynamic load of the pump station from the perspective of flow analysis, and the numerical simulation study was conducted using the RANS solver in conjunction with the VOF multiphase flow model. This research aimed to predict the force conditions experienced by the pump station during shut-down, start-up, and door-closed dredging operations, as well as to analyze the characteristics of the upstream and downstream flow fields. The findings revealed that: during the uniform closure process of the pump station, its hydrodynamic load shows a nonlinear increase; enlarging the gap between the bottom of the vessel and the riverbed can reduce the hydrodynamic load; the side thrust required for the pump station′s door-opening process is positively correlated with the water level of the river; during the pump station′s dredging process, the greater the distance between the bottom of the floating vessel and the riverbed, the larger the effective dredging range that can be achieved. The result indicate that the clearance between the bottom of the pump station, the flap of the water pump, and the lateral thrust power need to be adjusted and coordinated in a timely manner during the process of opening and closing the valve. At the same time, the conclusion can provide reference for risk assessment and resource management of similar engineering projects.

In order to solve the problem of difficulty in adapting to renewable energy and rapid load changes in generator start-stop scheduling, a generator start-stop optimization scheduling model with economic benefits as the goal and system safety and stability as the constraint is proposed on the basis of commonly used scheduling schemes. Besides, the particle swarm algorithm is introduced to linearize the model to reduce the required solving time and improve the solving efficiency. The proposed method was simulated and verified by IEEE-30 node system under the condition that the system hot standby ratio was 60%, respectively. The proposed generator start-stop scheduling optimization method has high accuracy and efficiency. Compared with the current generator start-stop scheduling method, the method proposed has an error of less than 5% and can save more than 50% of calculation time.

The variation of water and sediment in rivers is related to the health and function of rivers, and also reflects the environmental changes in the river basins. To understand the water and sediment variation and the influence of human activities in rivers of the arid inland areas in China, the Tarim River, Heihe River, and Shule River are selected, which are representative rivers in arid inland areas of China. The cumulative curve method and the M-K test are used to systematically analyze the change characteristics of annual runoff and annual sediment transport at representative hydrological stations in these rivers from 1950 to 2020, and explores the main factors affecting the water and sediment changes in arid inland river basins. The result indicate that the annual runoff at the representative hydrological station of the Tarim River exhibits no trend variation, whereas the annual sediment discharge presents a significant decreasing trend. The annual runoff at the representative hydrological station of the Heihe River shows a significant increasing trend, while the annual sediment discharge shows a significant decreasing trend. The annual runoff at the representative hydrological station of the Shule River displays a significant increasing trend, and the annual sediment discharge shows an increasing trend. The main factors affecting the change of runoff and sediment in arid inland rivers include climate environment, reservoir construction, watershed diversion and river overflow, soil and water conservation, unreasonable exploitation and utilization of watershed, and imperfect watershed policies and management.

In order to understand the fish passing effect of the fishway of Shawan Hydropower Station, this study carried out the passing and reentry tests in the fishway.Spinibarbus sinensis was taken as the research object, the tracing behavior of marked fish was recorded by installing(Passive Integrated Transpondere, PIT) monitoring equipment in the fishway. The result showed that a total of 284 fish belonging to 2 orders, 4 families, 13 genera and 15 species were collected during the investigation period. The dominant species(IRI>1 000) under the dam were C.fuscoguttatus, Pseudorasbora parva, Onychostoma belcheri, Scleroderma brachygnathus, Scleroderma labeo and Scleroderma labeo. A total of 258 fish species were collected in the fishway, belonging to 10 genera, 2 families and 1 order. The dominant species(IRI>1 000) in the fishway were Epinephelus acuminatus subsp.major, Leptobagrus przewalskii, Gobiocypris rarus, Hemibarbus labeo and Pseudorasbora parva. During the monitoring period, a total of 1 848 labeled fish signals were obtained, a total of 221 labeled fish were monitored, and 70 fish were not monitored.The upward rate of the marked fish was 36.08%, the reentry rate was 58.42%, and the pass rate was 18.10%. During the monitoring period, the number of signals monitored during the day(8:00—20:00) was higher than that at night(20:00—8:00), and the most frequent periods of fishway use were 10:00—11:00,15:00—16:00 and 16:00—17:00. This study can provide a reference for the study of fish passage effect of domestic fish passage facilities.

[Objective] Implementation of the Ten-Year Fishing Ban policy may alter fish diversity and niche characteristics of dominant species in spawning grounds within the National Nature Reserve for Rare and Endemic Fish in the Upper Yangtze River. This study initiated continuous monitoring of natural spawning habitats from February 2022 to assess these ecological changes. [Methods] Environmental DNA(e DNA) metabarcoding was employed to analyze fish species composition, biodiversity patterns, and niche parameters of dominant species. Water sampling followed the CEN/TS 19461 standard across five monitoring transects(ZT1-ZT5). [Results] The e DNA analysis detected 45 species of fish belonging to 38 genera, 13 families, and 3 orders were detected through environmental DNA(e DNA) in this survey, including 10 species endemic to the upper reaches of the Yangtze River, such as Procypris rabaudi and Myxocyprinus asiaticus. The fish community was mainly composed of bottom-dwelling, settling ovum-producing, omnivorous fish. The variation ranges of the Chao1 index, ACE index, Shannon index, and Simpson index are 736~996, 719~ 965, 1. 58 ~ 3. 23, and 0. 83 ~ 0. 99, respectively, indicating that fish species in spawning sites are abundant and community distribution uniformity is high. All indexes are highest at ZT1 monitoring points. Cluster analysis showed that, at a certain similarity level, fish community types in spawning sites could be basically divided into two groups: ZT1, ZT3, and ZT5 clustered together, and ZT2 and ZT4 clustered together, indicating similar fish community habitats. There are 9 dominant fish species in typical deep pool habitats in the reserve, with niche widths(Bi) ranging from 1. 13 to 3. 87. The dominant fish species are broad and medium niche fish, such as Cyprinus carpio and Hemiculter tchangi, with the niche overlap index(Oik) of some dominant fish species reaching more than 0. 95. This indicates fierce competition for resources among the fish in this spawning ground. [Conclusion] The Zhutuo spawning ground demonstrates high species richness with homogeneous community structure and intense resource competition. This study establishes an e DNA-based monitoring framework that enhances conventional survey method, providing critical baseline data for adaptive management under the fishing moratorium regime.

The aim was to explore the current status of the ecological buffer zones in the Xiaoqing River, identify major ecological and environmental issues, and propose ecological protection and restoration measures. Through the investigation and analysis of different types of ecological buffer zones in the Xiaoqing River, it was found that the river faces severe canalization, road-like embankments, and the loss of estuarine wetlands as ecological and environmental problems. Targeted restoration strategies such as interference removal, habitat creation, plant community establishment, and estuarine wetland development were proposed. These strategies aim to reduce the impact of human activities on the river, enhance the ecological functions of the buffer zones, and strengthen their role as important ecological safety barriers. By implementing ecological engineering projects, it is possible to effectively curb soil erosion, intercept and purify non-point source pollution, and improve the ecological environment quality of the Xiaoqing River.

High quality water resources are crucial for the development of water diversion projects, and effective water monitoring and early warning can help continuously improve water quality and environment. To improve the quality level of water resources, on online water quality monitoring and intelligent warning systems for new water diversion projects are studied. An overall framework for water quality monitoring models is constructed. Specific evaluation indicators for monitoring models through processing water quality data are defined, and water quality monitoring models for water diversion projects are built. On this basis, temperature sensors, pH sensors, TDS sensors, and ORP sensors are set up and their operational functions are debugged to achieve the design of an online water quality monitoring and intelligent warning system. The experimental results show that the application of the above system can monitor and warn the water quality of water transfer projects based on abnormal conditions such as water temperature, redox capacity, dissolved solid mass, and pH value, which can provide reference for continuous improvement of water quality environment.

In order to understand the fish gathering effect of Longkoukou fish gathering and transportation system, eight target fish species were caught through regular operation of the fish gathering and transportation system. The results showed that the fish aggregating system had a good effect on aggregating schizothorax, but it was quite different from the monitoring result of the fish aggregating system in 2021. This indicated that in the same season, due to different influences of the surrounding environment, the fish aggregating system will have different effects on the same fish. The PIT experiment was conducted with Schizothorax wangchiachii, Schizothorax chongi(Fang) and Schizothorax prenanti as the main research objects, to study the effect of collecting fish after releasing in different parts of the collecting system. The results showed that during the experiment, 17 tagged fish were caught in the collecting hopper, 13 of them entered the collecting platform, and 23.08% escaped from the collecting platform. 8 tagged fish released at the entrance of the fish collecting platform entered the fish collecting tank, 9 fish stayed in the fish collecting platform, and the proportion of fish escaping from the fish collecting platform was 45.16%. Five tagged fish released at the foil entrance of the deep water net were detected to enter the fish collecting platform, and the uplink rate was 16.67%. The result show that the Longkou fish collecting system has a certain effect of collecting fish. The research can provide reference for the transformation of Longkou fish collecting system and the research on the effect of domestic fish collecting system.

Long-distance water diversion projects are of great significance for alleviating regional water resource shortages and promoting regional economic and social development. Cascade pumping stations are key facilities to ensure the normal operation and efficient water transfer of these projects. Taking the informatization construction of the cascade pumping station group on the Shandong main line of the East Route of the South-to-North Water Transfer Project as an example, a knowledge-driven intelligent operation and maintenance management platform for cascade pumping stations was proposed. By analyzing the informatization construction needs of the cascade pumping station group and sorting out the relationships between actual engineering objects, a knowledge graph for the operation and maintenance of the cascade pumping station group is constructed. This enables intelligent management and optimized scheduling of heterogeneous multi-source data during the operation and maintenance of the pump station group. The research results show that this platform can improve the efficiency and reliability of the cascade pumping station group, reduce faults and losses, and achieve intelligent management during the operation and maintenance process.

With the development of the new generation of artificial intelligence technology, machine learning and deep learning frameworks have become important tools for developing and promoting artificial intelligence applications. On the premise of fully considering the limitations of computing resources of end devices, a video monitoring intelligent agent for pumped storage power stations based on cloud management edge end collaboration was proposed to solve the problem of traditional reliance on cloud data centers for intensive computing. Through the hierarchical deployment of algorithm models and the cloud management side to side collaboration mechanism, the problems of the video surveillance agent in the pumped storage power plant in computing power, network, storage, etc. are solved to a great extent, the high latency and high energy consumption caused by the transmission of large amounts of data over a long distance WAN are reduced, the agent edge computing mode is optimized, and the ability to apply AI technology with high computational complexity is improved, Improve the real-time application level of video monitoring intelligent agents in pumped storage power stations.

Water level measurement technology plays an important role in the operation of ship locks, and fiber optic grating sensors, as a new type of passive sensor, have great potential in the field of ship lock water level measurement. In order to establish a precise and reliable ship lock water level measurement system, a cascade arrangement scheme for the fiber optic grating water level measurement system in the ship lock was designed, which is easy to be connected in series, combined with the water level change characteristics during the operation of the ship lock. This scheme can further improve the actual measurement accuracy when measuring the water level difference inside and outside the ship lock, while the accuracy of the sensor itself is fixed. Based on this layout plan, a calibration algorithm was designed for zero drift and slope drift of the water level gauge. The calibration algorithm runs during the filling and discharging of the ship lock, and the water level gauge is calibrated step by step. In addition, a data fusion algorithm based on the Kalman filter principle was designed for the effective water level gauge data in the cascade layout scheme, and the effectiveness of the algorithm was verified through simulation.

China is endowed with a substantial reservoir of small hydropower resources. Since the 1980 s, the State Council has been instrumental in the advancement of rural hydropower development, successfully completing the electrification of over 1 500 counties. The country's installed capacity of small hydropower stations has reached a remarkable 73 000 megawatts(MW), representing over half of the global installed capacity of small hydropower. This achievement has significantly contributed to the economic and social advancement of rural areas. Nevertheless, as a consequence of economic development and environmental awareness, the role of small hydropower has been gradually marginalized, and the existing historical problems have not been effectively solved. A basic data platform of rural hydropower in China is employed to explore the feasibility of green transformation, modernization, and upgrading of small hydropower.It also analyzes the hydropower expansion mode and the feasibility of hybrid pumping and storage transformation under the condition of a high proportion of new energy to the grid. Furthermore, it puts forward a transformation planning plan for the hydropower resource-rich area of Southern Zhejiang Province and analyzes the technical economics of hydropower stations of different scales. It is demonstrated that through the implementation of reasonable efficiency enhancements and expansion renovations, the aged hydropower station can markedly enhance its energy efficiency, augment its power generation capacity, and enhance its safety and environmental benefits.

In the context of the implementation of the “dual carbon” goal and the “dual control” system, in order to more objective ly reflect the environmental impact and environmental benefits of hydropower projects, it has become inevitable to incorporate carbon emission indicators into the environmental impact assessment system of hydropower projects. However, at present, most hydropower projects lack measured data on carbon emissions, making it difficult to carry out more systematic environmental impact assessment research. Using the Jinping I Hydropower Station on the Yalong River as a case study, relevant parameters from six domestic hydropower projects are collected and standardized. A fuzzy clustering approach is then applied to estimate the carbon emissions of hydropower stations lacking measured data. The result show that the fuzzy clustering method can more accurately and quickly quantitatively predict the carbon emissions of hydropower stations, thereby providing a more scientific basis for environmental impact assessment work.

As a renewable and clean energy source, hydropower plays an irreplaceable role in the supply of electricity. Due to the special characteristics of the hydropower station, it has undertaken a certain water resources allocation tasks, such as agricultural water use, industrial water use, municipal water use and other water supply tasks. How to balance the contradiction between water resources allocation and power generation scheduling during the operation of hydropower plants is one of the research hotspots in this field. Joint optimal scheduling of water resources and power generation of hydropower plants in the operation process of hydropower plants is an effective way to solve this problem. The purpose is to review the research result in the field of joint optimal scheduling of water resources and power generation in hydropower stations in recent years, and to discuss the hot direction of future research in this field for providing some reference to relevant research.

With the increasing global carbon emission reduction requirements, ship lift navigation scheduling system plays an increasingly important role in improving navigation efficiency, reducing empty ship trips and reducing carbon emissions. In order to optimize the navigation management of a ship lift, taking a dam as the research object, a set of intelligent navigation scheduling system based on AIS ship positioning, video surveillance, three-dimensional GIS and automatic sluice scheduling was studied and designed. The results show that the improved system can significantly improve the traffic scheduling efficiency, and the scheduling efficiency optimization range reaches more than 35%. The system performed well in reducing the number of empty ships to 5 after 800 iterations, significantly better than the 82% of traditional systems. In terms of carbon emission control, the carbon emission under complex conditions is as low as 120.78 kg.

To achieve unified construction and operation of water supply and drainage throughout Jiande city, unify the development and utilization of water resources, and fully promote common prosperity throughout the city, integrated water management reform was carried out based on the existing water infrastructure. The current situation and problems of urban and rural water affairs in Jiande City were thoroughly analyzed, the goals and principles of water affairs reform were determined, and the construction and operation of the city's water supply and drainage facilities were comprehensively considered through reform measures such as establishing a water conservancy and water affairs group company, clarifying the responsibilities of government and enterprises, promoting water price and water fee reform, and accelerating the construction of water conservancy and water affairs projects. The integrated reform of water resources in Jiande City has achieved good reform result, such as smooth management system, unified construction and management, smooth water supply and drainage, high-quality services, and water prices on the same network and at the same price. It has achieved the goals of ensuring urban and rural water supply safety, fully utilizing water resources, and preserving and increasing the value of state-owned assets. It has comprehensively improved the support and guarantee capacity of water resources in Jiande City, fully achieving the economic, social, and environmental benefits of limited water resources. It has established a new model for the integrated reform of water resources in Jiande City, and provided a model for water integration reform for other regions.

The risk of ship impact is growing for various types of water conservation facilities due to the fast-growing inland river navigation. Compared with general mass concrete water-retaining structures, e.g. dams, gate structures are thinner and thus take higher failure risks in ship-impact events. Consequently, gate structures are generally recognized as weaknesses among water-retaining structures. Unfortunately, no mature method are available for quantitative assessment of failure risks to gate structures in ship-impact events. A risk assessment study of a radial gate structure was conducted. A multi-source information fusion assessment approach based on the combination of weights, the cloud model and the D-S evidence theory was proposed. Finite element analysis was carried out to provide the data input for the risk assessment.In the current case of the ship tonnage between 200-3 000 t and the ship's speed between 1-8 m/s, the failure risk of the radial gate subjected to ship collisions is ranked as Class II. The gate should have some pitfalls in ship-impact events but can maintain its safe operation. The proposed method can directly present the gate's risk level, thus achieving quantitative assessment of failure risks to gate structures in ship-impact events. The assessment result can serve as a scientific foundation for the navigation safety management of water conservancy facilities and the formulation of the corresponding emergency plans.

At present, the industrial control technology of ship lock has gradually failed to meet the current needs in the aspects of data interaction between different systems, hierarchy definition between systems and network security risks. By analyzing the service flow of ships passing through locks in the Three Gorges River section, a concept of “parallel lock” is put forward which integrates intelligent management, intelligent operation and intelligent supervision. Through the construction of a parallel lock management system for ships passing through the lock area, the whole process of ships beginning to declare to the final departure from the lock area is manifested and digitized, and then the entire ship passing through the lock service is comprehensively monitored and intelligently managed, making the lock industrial control technology further intelligent navigation on the existing basis.

Connected water level is an important factor affecting the efficient utilization of water resources in Dadu River Basin. Based on the latest real and measured data, the connected relationship of Tongjiezi-Shawan Power Station in Dadu River Basin under the minimum discharge flow was analyzed by using hydrological and hydrodynamic simulation method, and the corresponding minimum discharge flow guarantee method was proposed. The result show that, under the influence of long-term scouring after reservoir operation, the stage-discharge relation below the Tongjiezi dam shows a right deviation compared with the design stage, and the corresponding water level is relatively low under the same flow. The backwater at the end of Shawan Reservoir has a jacking effect on the water level below Tongjiezi Dam, and the jacking effect is more obvious when the water level of Shawan Reservoir is above 431 m. The latest data shows that Tongjiezi-Shawan has an incomplete connected relationship, with a connected water level of 430.47 m, which is 1.53 m lower than the designed connected water level of 432 m. Adopting the new connected water level can improve the efficiency of water resource utilization between upstream and downstream cascades while meeting the minimum discharge demand.

The water economic operation system is an important tool for water resources management and can greatly improve the operating efficiency of power stations. However, user behavior directly affects the system's operating status and data accuracy. Through real-time monitoring and analysis of user behavior via system logs, potential security threats can be discovered in a timely manner. The commonalities of abnormal user behaviors found in system logs were studied. A Transformer-based user abnormal behavior identification model for water economic operation system(T-UABI-WEOS) was proposed. Without sacrificing the original information of the data, the feature fusion preprocessing method is used to optimize the expression form of the data, so that the interaction between features is effectively reflected, rather than simply being treated independently. Considering the imbalance of user behavior data, a variational auto-encoder(VAE) model to learn from normal sequence data was introduced. The trained VAE model then generates simulated abnormal sequence data to balance the dataset, thus enhancing the training effect of the model. Experimental result show that the proposed method achieves a 6% improvement in prediction accuracy over traditional data preprocessing method. Additionally, the experiment compared different deep learning models, and the model T-UABI-WEOS showed higher accuracy and lower false alarm rate. The result demonstrated that T-UABI-WEOS achieved higher accuracy and a lower false alarm rate. The research result provide scientific decision-making support for the electric power industry. By identifying abnormal user behavior in real-time, potential security threats can be discovered promptly, allowing for the implementation of corresponding preventative measures. The approach can better address network security incidents and ensure the stable operation of the power grid, ultimately contributing to national security and stability.

Aiming at major dangerous phenomena about medium and small reservoirs that have been reinforced in recent years, and major dangerous situations such as dam-collapsed dams and landslides, the impact of investigation specifications on reinforcement projects on reservoirs have been discussed. Based on the danger elimination and reinforcement data of medium and small reservoirs in our country, the impact of investigation specifications on the reinforcement projects of medium reservoirs through examples, and compares the differences between the Specification of engineering geological investigation for medium-small water conservancy and hydropower development(SL 55—2005) and three normative documents on the investigation regulations for danger elimination and reinforcement of small reservoirs were analyzed. The result show that:(1) 62.4% of the country's reinforcement projects of medium reservoirs without appropriate investigation specifications, it has a profound influence on the dam safety of the reinforcement projects of medium reservoirs.(2) The two normative documents and the individual provisions of SL 55—2005 have had an immeasurable and far-reaching impact on the dam safety of 99.3% of the country's reinforcement projects of small reservoirs.(3) The SL 55—2005 does not guarantee the quality of specification and design for the hundreds of reinforcement projects of medium reservoirs and reinforcement that need to be completed in the near future, one normative document will ensure the quality of the reinforcement of small reservoirs reinforcement in the implementation. The result show that it is urgent to revise and perfect SL 55—2005 to ensure the safety of medium and small reservoirs dams.

In the creation of benchmark tables relying on experts, there exists freely controlling the degree of deduction within the deduction interval. In response to the problem of inconsistent differentiation caused by the importance of factors, the proportion of total scores, and the consistency of deduction intervals, principal component analysis(PCA) is used to reconstruct the “Evaluation Criteria” and establish a feature matrix as input variables. GA genetic algorithm is used to improve the BP neural network for fitting verification. The result indicate that the higher the degree of dispersion of the factors in the Evaluation Criteria, the more representative they are of the actual situation of creation; The GA algorithm further enhances the generalization ability and accuracy of the BP neural network by establishing a mapping relationship between the explanatory target and the explanatory fitness kernel function. The improved GA-BP neural network algorithm model has a fitting accuracy of 98.78%; The fitted R² of the “Evaluation Criteria” after reconstruction is as high as 0.953, which has improved by 0.107 compared to before reconstruction and has better fitting accuracy. At present, there is relatively little research on the deconstruction and reorganization of water conservancy engineering standardization from the perspective of factor dispersion. The research conclusion of this article can effectively assist in the creation of standardized management for reservoirs in Guizhou Province and the subsequent revision of the “Evaluation Criteria”.

Artificial Intelligence Generated Content(AIGC) technology, as an emerging field combining artificial intelligence with generative computation, is rapidly evolving through method such as machine learning, deep neural networks, and generative models. It extracts elements from massive datasets and generates complex content, bringing disruptive transformations to numerous sectors. In the domain of hydraulic engineering design, AIGC technology demonstrates extensive potential applications. These include high-precision river flow predictions based on Long Short-Term Memory(LSTM) neural networks, intelligent water resource management and integrated basin governance using machine learning algorithms, and enabling the entire lifecycle design of hydraulic projects through intelligent systems. However, the unique nature of engineering projects, algorithm applicability, data quality, infrastructure development, talent cultivation, and information security also pose significant challenges to the application of AIGC technology in hydraulic engineering design. Continuous interdisciplinary technological innovation, industry data accumulation, and professional talent development are crucial in addressing these challenges, facilitating the transformative role of AIGC technology in promoting intelligent, refined, and sustainable development in hydraulic engineering design.

The misalignment detection scheme for the miter gate of a large ship lock using image recognition technology was discussed. High-definition image acquisition equipment was used. Real-time detection of gaps and dislocations in the miter gate was achieved through pre-processing, feature extraction, and SVM classifier training. Field prototype testing and error analysis have demonstrated the practicality and effectiveness of the scheme, meeting the practical application requirements of ship locks.

In ecological slope protection, plant roots reinforce soil by reinforcing or anchoring, and root size directly affects the soil consolidation efficiency of plants and slope stability. With root diameter and root length as variables, the displacement response of root-soil complex under pull-out and horizontal coupling loads under different root sizes was analyzed by numerical method. By comparing the displacement characteristic curves of root, soil and root-soil complex under pull-out and horizontal loads, the influence of root diameter and root length on the deformation of the complex was analyzed, and the displacement evolution law of the complex under different root sizes was clarified. The result show that the influence of root diameter on the deformation of the root-soil complex is weak under pull-out horizontal load, but the larger the root length, the smaller the deformation of the root-soil complex. When the root length is short, the displacement increment of the root-soil complex is mainly concentrated on the soil on both sides of the root wall. With the increase of root length, the displacement increment of soil on both sides of root wall also increases. Longer roots provide a larger anchoring area and are therefore better able to disperse and carry loads. In the case of short roots, soil deformation mainly occurs at the near end of the root, while long roots can make the deformation pattern more uniform, affect the soil at a longer distance, and improve the stability of the whole system.

The volume dialation effect is a significant characteristic of rock volume change under triaxial compression conditions, and is an important manifestation of the nonlinear expansion of rock volume. In order to examine the dialation characteristics of rock, analyze the influence mechanism of plastic characteristics and stress level on the dialation characteristics, and explain the deviatoric stress-strain curve characteristics of the rock in the whole process, taking the silty mudstone of a water diversion project in southwest China as the research object, a study was carried out. In the triaxial compression test under the confining pressure level of 1~25 MPa, the Mohr-Coulomb strength criterion and plastic parameters were introduced to study the dialation characteristics of the rock. The results show:(1) The dialation stress and residual stress of the rock are 0.65 and 0.58 of the peak stress respectively, and various strength indicators have an obvious linear relationship with the confining pressure level, which is consistent with the Mohr-Coulomb strength criterion;(2) After dialation occurs, the internal friction angle and cohesion of the rock experienced changes that first increased and then decreased as the plastic parameters increased, and the change characteristics had a certain degree of asynchrony. The fitting model based on the Mohr-Coulomb strength criterion and plastic parameters can Describe the deviatoric stress-strain curve of the whole process after the rock dialation occurs;(3) The dialation angle and dialation index decrease in a negative exponential manner as the confining pressure increases, and the rupture surface inclination angle gradually increases with the increase of the confining pressure. and gradually stabilized.The deformation process of rock after dialation is closely related to the stress level and plastic properties, and the confining pressure has an inhibitory effect on rock dialation.

Pipelines in China's mountainous areas are widely distributed, running through the northwest to the southeast and the central, southwest, northeast and other regions, often inevitably passing through complex and steep mountainous areas. It is found that the common geological disasters in China's pipeline inspection include collapses, landslides, debris flows, water damage, etc. Due to the characteristics of high pressure, flammability and explosiveness, once a geological disaster occurs, it is easy to cause casualties, property losses and bad social impact. Therefore, it is of great significance to carry out research on the risk management and control technology of geological disasters in mountainous areas. Bibliometric and categorical statistics are used to analyze the differences between domestic and foreign risk management and control technologies and other linear engineering technologies such as pipelines and highways, railways, power grids and land. The risk management and control technologies studied include identification technology, risk assessment technology, monitoring and early warning technology, and prevention and control technology. By condensing the important technical characteristics of geological disasters of domestic and foreign linear engineering pipelines, and combining their advantages and disadvantages, the technologies worthy of reference for China's mountainous pipelines are summarized. These technologies can be used as scientific and reliable protection and control guidance for mountain pipeline engineering in China, and provide strong support for ensuring the safe operation of mountain pipelines.

As a critical component in the construction of diversion-type power stations, water diversion tunnels require comprehensive advanced geological prediction to ensure safe water diversion tunnels require comprehensive advanced geological prediction to ensure safe excavation and timely completion. This study focuses on a deep-buried water diversion tunnel in western Sichuan, where complex geological conditions such as high in-situ stress, fault fracture zones, and abundant groundwater were encountered during excavation. By integrating geological analysis, TRT(Tunnel Reflection Tomography) method, Transient Electromagnetic Method(TEM), and Ground Penetrating Radar(GPR), we propose a three-dimensional geological prediction approach based on an advanced geological forecasting platform. The implementation procedure consists of three phases: First, 3D seismic wave method is employed to identify tunnel sections with anomalous geophysical responses indicating unfavorable geological features. Second, multi-angle TEM verification and three-dimensional integration of geological and geophysical data are conducted for these anomalous sections. Finally, precise prediction of adverse geological conditions ahead of the tunnel face is achieved through GPR detailed detection and supplementation of prior geological data. Application of this method in the western Sichuan tunnel project revealed: In the section Stake(Tunnel) 6+950—6+867, surrounding rocks exhibited poor integrity with developed joint fissures, localized minor faults, moderately fractured to fragmented rock masses, and significant groundwater presence, classified as Class IV surrounding rock. The section Stake(Tunnel) 6+867—6+830 showed relatively poorer rock integrity with moderately developed joints, less groundwater, and localized fracturing, classified as Class III₂—IV surrounding rock. The result demonstrate that this 3D comprehensive geological prediction method effectively combines geological and geophysical approaches, integrating point-line-plane geophysical techniques. It successfully delineates the spatial distribution and development range of unfavorable geological features including fault fracture zones, joint fissures, and water-rich zones ahead of the tunnel face, providing reliable technical guidance for safe and efficient tunnel excavation.

As an important part of urban infrastructure, underground engineering structures are of great significance in the planning and design of underground space. The current status of safety and resilience technology for underground engineering structures is reviewed, and the existing problems and future development directions are discussed. The research background and significance of underground engineering structure safety and toughness technology are introduced. The existing research are summarized from the aspects of underground structure safety assessment, underground structure seismic toughness technology, underground structure damage identification and repair. Future development direction of underground engineering structure safety and resilience technology are described.

The geological conditions of the upper boundbelt of Jinsha River are extremely complex.The high position and long-runout geological disasters are the epitome of the geologica levolution in this area, which have for med many chain disasters similar to Baige landslide.High position and long-runout landslide has the characteristics of strong concealment, largescale, high suddenness and great destructive power.It is difficult to detect early due to the limitation of ground survey methods.Based on multi-optical remote sensing technology to carry out the Jinsha River upstream binding zone high remote landslide identification research, starting from the formation condition sand evolution process of high position and long-runout landslide, the comprehensive identification method of comprehensive remote sensing interpretation and halo disaster geological environment conditionanaly is adopted.Fourearly identification indexes of high position and long-runout landslide are stablished, which are image mark, topography mark, geological condition mark and human engineering activity mark.84 high position and long-runout landslides were identified int hestudy area.Through the identification results, the early identification indicators are further summarized, and the indicators are divided into three levels: basic conditions important conditions and auxiliary identification conditions.The research results provide the basis for the prevention and control of geological disasters and major engineering construction in the upper Jinsha River region, and also provide references for the early identification of high position and long-runout landslides in similaral pine valleyareas.

To investigate the impact of rain on the physical and mechanical components of accumulation body landslides, a physical model was created in the western of China. Rainfall is a primary factor in such landslides. By simulating typical rainfall effect, samples were taken at different elevations of the accumulation body physical model, and permeability and direct shear tests were carried out. The evolution of mineral content, porosity, permeability coefficient and shear strength parameters along the elevation are analyzed in detail. The results show that the porosity at the top of the slope surface is 2.2 times that at the bottom of the slope surface, and the content of SiO₂ and Al₂O₃ representing fine particles such as river sand and clay increases by about 7% and 3%.The permeability coefficient and internal friction Angle of accumulation body increase gradually with the increase of elevation, but the c value of cohesion shows the opposite law and gradually decreases. The permeability coefficient, internal friction Angle and cohesiveness of slope surface change more obviously than that of slope interior. Combined with the quantitative analysis of parameters and the observation of phenomena in the test process, it is shown that the runoff and seepage of rainfall promote the migration and accumulation of fine particles to the low elevation of the slope. The research process and result are of great significance to the stability analysis of accumulative landslides under rainfall conditions.

The study of slope stability problems under the influence of rainfall is a key link in the prevention and control of slope disasters. To explore the impact of fracture aperture on the stability of mudstone reservoir bank slopes, the finite element numerical simulation technique was used to investigate the changes in internal seepage characteristics of slopes with different fracture apertures under rainfall conditions, and to analyze the rules of the impact of crack aperture on their stability under different slope failure modes. The results show that under rainfall conditions, rainwater permeates into the interior along the fracture of the slope rock mass and forms a saturated area at the base of the slope, with the area of this region increasing as the fracture aperture increases. When the mudstone reservoir bank slope undergoes slip failure, the stability coefficient increases with the increase of the fracture aperture, and when the fracture aperture is greater than 0.75 mm, the safety factor of the slope reaches 1.2; when it undergoes layer slip-bending failure, the stability coefficient decreases with the increase of the fracture aperture, and when the fracture aperture is less than 0.15 mm, the safety factor of the slope reaches 1.4. It can be seen that the impact of fracture aperture on the stability of mudstone reservoir bank slopes is directly related to the failure mode of the slope.

In order to seasonally frozen regions, significant temperature fluctuations affect the mechanical stability and long-term durability of reinforced soil engineering in cold areas by changing the mechanical properties of the reinforced soil interface. This study uses the discrete element method PFC^3D software. A numerical simulation of the direct shear test was carried out for coarse-grained soil-geogrid indoor direct shear test at-5 ℃. The evolution process of macro and micro characteristics of geogrid reinforced coarse-grained soil in direct shear tests, such as single deformation force, porosity change, displacement and rotation of coarse-grained soil, and force chain stress field inside the soil, is revealed. The accuracy and practicability of the model are verified by comparing the simulation result with the laboratory test result. The results show that under the condition of-5 ℃ low temperature, with the increase of shear displacement, the deformation is gradually obvious, and the deformation of the longitudinal rib is significantly greater than that of the transverse rib. An in-depth analysis of the porosity changes of different sections inside the soil shows that the porosity decreases with the increase of shear displacement, and the porosity on the shear surface and below shows an asymmetric distribution pattern. The shear displacement is mainly concentrated around the shear surface, and the displacement is characterized by high left and low right. As the shear proceeds, a centrally symmetrical arch structure is formed inside the soil. The stress field of the soil is further explored. The strong chain is initially distributed along the wall to create a low-stress zone. After the stress peak, the contact force between the particles decreases, and the force chain is distributed along the diagonal. This distribution feature is closely related to the applied horizontal thrust. The research findings provides a theoretical explanation for the reinforcement mechanism of coarse-grained soil from the microscopic point of view and provides data support for the design parameters of reinforced soil engineering in seasonal frozen soil areas.

Reinforced soil slopes constructed in high altitude regions may face structural damage due to freeze-thaw cycles, material aging, and seismic activity. Therefore, it is crucial to conduct on-site monitoring of reinforced soil slopes during construction and service in high altitude areas to ensure the safety and stability of the project. A field test was conducted on a newly constructed 40-meter-high geogrid-reinforced soil slope in Qamdo, Xizang. The internal and external temperature, slope deformation, top settlement, vertical earth pressure and geogrid strain distribution of the reinforced soil high slope constructed in high altitude areas were analyzed. The engineering performance of the reinforced soil high slope in high altitude areas was discussed. The test results show that the internal temperature of the reinforced soil slope varies with the change of ambient temperature, with the boundary area of the slope being particularly sensitive to temperature changes. The lateral displacement of the slope surface increases sharply during construction and then gradually stabilizes, with the maximum lateral displacement occurring on the lowest slope surface, and the cumulative displacement is about 1.11% of the slope height. The slope surface settlement stabilizes graduall after construction, with the maximum incremental settlement of approximately 50 mm observed six months post-construction. Due to the construction of the upper substation and the increase of mechanical loads, the settlement of the slope top is still gradually increasing. The vertical earth pressure within the slope decreases gradually with increasing slope height, and along the direction of geogrid placement, it first increases and then decreases. The strain in the geogrid decreases gradually along the direction of geogrid placement and with increasing slope height.

Plant roots are widely known to provide mechanical reinforcement to soils against shearing and further increase slope stability. However, whether roots provide reinforcement to loess cyclic re-sistance and how various factors affect roots reinforcement during seismic loading have rarely been studied. The objective is to conduct a series of cyclic direct simple shear tests and DEM numerical simulation to investigate the cyclic behaviour of rooted loess. The effects of initial static shear stress and loading frequency on the cyclic resistance of root-soil composites were first investigated. After that, cyclic direct simple shear simulations at constant volume were carried out based on the discrete element method(PFC3D) to investigate the effects of root geome-try, mechanical traits and root-soil bond strength on the cyclic strength of rooted loess. It was discovered that the roots could effectively improve the cyclic resistance of loess. The cyclic resistance of the root-soil composite decreases with the increase of the initial shear stress, then increases, and improves with the increase of the frequency. The simulation result show that increases in root elastic modulus and root-soil interfacial bond strength can all enhance the cyclic resistance of root-soil composites, and the maximum cyclic resistance of the root-soil composite was obtained when the initial inclination angle of the root system was 90°.