A Special-shaped servo structural agent and undercutting construction method for shield tunnel ramp junction

Abstract

In the construction and renovation processes of underground spaces in dense urban environments, there is an increasing demand for space-intensive layouts and special-shaped cross-sections. To address the requirements for special-shaped cross-section design and lightweight structures, this study, against the backdrop of construction of underground road ramp junctions, proposes a servo structural agent for special-shaped cross-sections and its underground excavation method with no foundation pit construction by integrating traditional underground structures with intelligent perception and servo strut control. This agent embeds servo components into the structural system and performs active force control through sensing of stress and deformation. Compared with traditional structures, servo structural agent can adaptively balance the load changes induced by excavation, thereby reducing component size and deformation. On this basis, an undercutting construction method and process are proposed, utilizing dual shield tunneling parallel construction and underground excavation to replace the traditional large working shaft schemes. Through numerical simulations of typical conditions, the servo structural agent is shown to reduce maximum deformation by 30% and peak internal forces by 10%. The related work provides novel approaches for underground excavation construction and safety control in urban areas with dense underground road networks.

Graphical abstract

Keywords

servo structural agent / special-shaped cross-section / shield tunnel / undercutting construction / servo strut

References

[1] Broere W . Urban underground space: Solving the problems of today’s cities. Tunnelling and Underground Space Technology, 2016, 55: 245–248

[2] Fang TGuan LFeng L. Research on undercutting method of shield-driven underground expressways in urban core zones with soft soil layers. Chinese Journal of Underground Space and Engineering, 2022, 18(S2): 792–799, 812 (in Chinese)

[3] Yang H , Zhou W , Liu C , Jiang X , Yu L . Large-scale shaking table test of seismic response laws for a shallow double-arch tunnel under unsymmetrical pressure with a damping layer. Advances in Civil Engineering, 2020, 2020(1): 8899276

[4] Hsiao F Y , Wang C L , Chern J C . Numerical simulation of rock deformation for support design in tunnel intersection area. Tunnelling and Underground Space Technology, 2009, 24(1): 14–21

[5] Li Y , Jin X , Lv Z , Dong J , Guo J . Deformation and mechanical characteristics of tunnel lining in tunnel intersection between subway station tunnel and construction tunnel. Tunnelling and Underground Space Technology, 2016, 56: 22–33

[6] Tan Z , Li Z , Tang W , Chen X , Duan J . Research on stress characteristics of segment structure during the construction of the large-diameter shield tunnel and cross-passage. Symmetry, 2020, 12(8): 1246

[7] Lu P , Yuan D , Luo W , Jin D , Liu M . Centrifugal model test study on the mechanical characteristics of shield tunnels influenced by different types of openings for cross passages. Applied Sciences, 2022, 12(13): 6421

[8] Ma C , Peng F . Some aspects on the planning of complex underground roads for motor vehicles in Chinese cities. Tunnelling and Underground Space Technology, 2018, 82: 592–612

[9] Cao L , Fang Q , Zhang D , Chen T . Subway station construction using combined shield and shallow tunnelling method: Case study of Gaojiayuan station in Beijing. Tunnelling and Underground Space Technology, 2018, 82: 627–635

[10] Hiroshi D , Akira S , Miyama D . Design and construction of enlarging shield tunnel sections of large dimensional shield tunnels for the on-open-cut method. Tunnelling and Underground Space Technology, 2006, 21(3): 249

[11] Namikawa YK TTerashima JInoue YKoseki MMiyashita Matsumoto . Construction of expressway branch junction structure using non-cut-and- cover enlargement method to combine two shield tunnels in sedimentary soft rock. In: ITA-AITES Wond Tunnel Congress. London: Taylor & Francis Group, 2016

[12] LI YZhang KHuang CLi ZDeng M. Analysis of surface subsidence of tunnel built by pipe-roof pre-construction method. Rock and Soil Mechanics, 2011, 32(12): 3701–3707 (in Chinese)

[13] LI YZhang KHuang C. Monitoring of lining structure of tunnels built by using pipe-roof pre-construction method. Chinese Journal of Geotechnical Engineering, 2012, 34(8): 1541–1547 (in Chinese)

[14] Zhang P , Ma B , Zeng C , Xie H , Li X , Wang D . Key techniques for the largest curved pipe jacking roof to date: A case study of Gongbei tunnel. Tunnelling and Underground Space Technology, 2016, 59: 134–145

[15] Liu X , Liu Y , Qu W , Tu Y . Internal force calculation and supporting parameters sensitivity analysis of side piles in the subway station excavated by Pile-Beam-Arch method. Tunnelling and Underground Space Technology, 2016, 56: 186–201

[16] Xu X , Li Z , Fang Q , Zheng H . Challenges and countermeasures for using pile-beam-arch approach to enlarge large-diameter shield tunnel to subway station. Tunnelling and Underground Space Technology, 2020, 98: 103326

[17] Zhang M , Liu Y , Fan L , Li P . Performance of constructing a double-deck subway station by combining the shield method and cavern–pile method. Tunnelling and Underground Space Technology, 2017, 67: 120–131

[18] Yang Y , Liao S , Liu M , Wu D , Pan W , Li H . A new construction method for metro stations in dense urban areas in Shanghai soft ground: Open-cut shafts combined with quasi-rectangular jacking boxes. Tunnelling and Underground Space Technology, 2022, 125: 104530

[19] Zheng Z , Xue X , Su D , Chen J , Qiu T , Chen P , Xie D , Su L , Chen W , Huang S . et al. Instability mechanism and reinforcement measures for segments of Ultra-Large diameter shield tunnels when constructing cross passages by mechanical methods. Tunnelling and Underground Space Technology, 2024, 154: 106125

[20] Jia P , Nie Y , Shi P , Jiang X , Lu B , Zhao W . Flexural performance of a novel pipe-roof structure and optimization of key parameters. Journal of Constructional Steel Research, 2022, 199: 107594

[21] Liu X , Gao Y , Ramos G , Turmo J , Zhu Y . Full-scale tests on segmental lining with mechanically cut cross-passage opening. Tunnelling and Underground Space Technology, 2024, 151: 105874

[22] Wang SZhu YYu Z. Design of automatic hydraulic support trolley for overlapped shield tunnel based on SolidWorks Simulation. Tunnel Construction, 2019, 39(2): 294–301 (in Chinese)

[23] Di H , Guo H , Zhou S , Chen J , Wen L . Investigation of the axial force compensation and deformation control effect of servo steel struts in a deep foundation pit excavation in soft clay. Advances in Civil Engineering, 2019, 2019(1): 5476354

[24] Li M , Demeijer O , Chen J . Effectiveness of servo struts in controlling excavation-induced wall deflection and ground settlement. Acta Geotechnica, 2020, 15(9): 2575–2590

[25] Nangulama H K , Jian Z . Deformation control monitoring of basement excavation at field construction site: A case of hydraulic servo steel enhancement geotechnology. Advances in Civil Engineering, 2022, 2022(1): 6234581

[26] Xu C , Hou J , Liu B , Lei F , Song L . Research on coordinated relationship between deformation and force in shaft foundation pit support structures. Buildings, 2024, 14(11): 3438

[27] Zhao Y , Chen X , Hu B , Huang L , Lu G , Yao H . Automatic monitoring and control of excavation disturbance of an ultra-deep foundation pit extremely adjacent to metro tunnels. Tunnelling and Underground Space Technology, 2023, 142: 105445

[28] Sun YLiu MLu PChen RPang K. Review of key technical issues in construction of cross passage in shield tunnel. Modern Tunnelling Technology, 2021, 58(S1): 293–302 (in Chinese)

[29] Nangulama H K , Jian Z , Xiao Z , Zhu J , Yuan F . Stage-by-stage control effect field analysis of steel material servo enhanced support system on lateral displacement and bending moment during deep basement excavation. Case Studies in Construction Materials, 2022, 16: e01068

[30] Haundi T , Nangulama H K , Mbewe V R . Site characterisation, deep basement support, construction, and deformation control. Geotechnical and Geological Engineering, 2024, 42(3): 1611–1622

[31] Zheng G , Huang J , Diao Y , Yan Y , Jiao C , Zhang L , Jia J , Peng J . Field investigation of deflection characteristics and control strategies of a short floating pile adjacent to deep excavation. Journal of Geotechnical and Geoenvironmental Engineering, 2025, 151(4): 05025001

[32] Li S , Wang F , Le Y , Que Q , Su Y , Lin H . Design and deformation pattern simulation of deep excavation support structures. Frontiers in Earth Science, 2024, 12: 1416957

[33] Dong X , Zhou F , Yoo C , Wang X , Zhu R . Suggested deformation control approach for braced excavations incorporating corner and soil arching effects. Tunnelling and Underground Space Technology, 2026, 167: 107059

[34] Guo X , Wang B , Wang Z , Yu W , Ma Z , Yang T . Application of the microclamped Fiber Bragg Grating (FBG) sensor in rock bolt support quality monitoring. Advances in Civil Engineering, 2020, 2020(1): 3419835

[35] Liu Q , Guo J , Liu L , Huang K , Tian W , Li X . Optimization analysis of smart steel-plastic geogrid support for tunnel. Advances in Civil Engineering, 2020, 2020(1): 6661807

[36] Zhang X , Zhu H , Jiang X , Broere W . Distributed fiber optic sensors for tunnel monitoring: A state-of-the-art review. Journal of Rock Mechanics and Geotechnical Engineering, 2024, 16(9): 3841–3863

[37] Li X , Xue W , Fu C , Yao Z , Liu X . Mechanical properties of high-performance steel-fibre-reinforced concrete and its application in underground mine engineering. Materials, 2019, 12(15): 2470

[38] You X , Yan G , Alnowibet K A , El-Meligy M . Artificial neural network-enhanced mathematical simulation based on Carrera unified formulation for dynamic analysis and structural integrity assessment of advanced nanocomposites reinforced tunnel structures. Mechanics of Advanced Materials and Structures, 2025, 32: 4882–4892

[39] Li T , Shu J , Wang Y . Deformation prediction of underground engineering support structures via the ST-CNN-LSTM model. Journal of Civil Structural Health Monitoring, 2025, 15(6): 1901–1919

[40] Barbati M , Bruno G , Genovese A . Applications of agent-based models for optimization problems: A literature review. Expert Systems with Applications, 2012, 39(5): 6020–6028

[41] Mazzetto S . Interdisciplinary Perspectives on Agent-Based Modeling in the Architecture, Engineering, and Construction Industry: A Comprehensive Review. Buildings, 2024, 14(11): 3480

[42] Sun M , Staszewski W J , Swamy R N . Smart Sensing Technologies for Structural Health Monitoring of Civil Engineering Structures. Advances in Civil Engineering, 2010, 2010(1): 724962

[43] Korkmaz S . A review of active structural control: challenges for engineering informatics. Computers and Structures, 2011, 89(23–24): 2113–2132

[44] Xi Z , Chen W , Guo X , He W , Ding Y , Hong B , Zhang M , Wang J , Jin S , Zhou E . et al. The rise and potential of large language model based agents: A survey. Science China. Information Sciences, 2025, 68(2): 121101

[45] Azad M M , Kim S , Cheon Y B , Kim H S . Intelligent structural health monitoring of composite structures using machine learning, deep learning, and transfer learning: A review. Advanced Composite Materials, 2024, 33(2): 162–188

[46] Seventekidis P , Giagopoulos D , Arailopoulos A , Markogiannaki O . Structural Health Monitoring using deep learning with optimal finite element model generated data. Mechanical Systems and Signal Processing, 2020, 145: 106972

[47] Panda J , Chopra M , Matsagar V , Chakraborty S . Continuous control of structural vibrations using hybrid deep reinforcement learning policy. Expert Systems with Applications, 2024, 252: 124075

[48] Wang S , Xu L , Zhang X , Long L , Zhuang X . Development and field analysis of a novel servo concrete bracing system for deep foundation pit excavation. Buildings, 2024, 14(6): 1674

[49] Wang C , Lin G , Yao H , Ding H , Tang X , Lin Z , Wang X . Observation and analysis of deformation control performance of hydraulic servo steel support for a soft soil pit—A case study of a pit project in Hangzhou. Buildings, 2025, 15(7): 1002

[50] GB/T 50010-2010. Code for Design of Concrete Structures. Beijing: China Architecture and Building Press, 2010

[51] Sun JBai T. Control methods for lateral deformation of retaining structure of deep foundation pit in soft soil. Tunnel Construction, 2019, 39(S2): 308–317 (in Chinese)

[52] Wang ZLi ZCai LLi HXu H. Research on application technology of steel support servo system for foundation pit. Tunnel Construction, 2020, 40(S2): 10–22 (in Chinese)

[53] Li HLiao STang YShen M. Deformation characteristics and stress path analysis of divided foundation pit in soft soils. Journal of Tongji University (Natural Science), 2021, 49(8): 1116–1127 (in Chinese)

RIGHTS & PERMISSIONS

Higher Education Press