Taizhou Bridge is the first three-tower two-span suspension bridge with the main span over 1 000 m in the world. The structural system of the stiffening girder is complicated and unique. Improvement and innovation have been made in detailed structure design of the stiffening girder based on Runyang Bridge according to the structural character of three-pylon two-span suspension bridge. In this paper, the structural system, structure design, structure calculation, manufacturing and erection of the stiffening girder are introduced.
The steel box girder of Taizhou Bridge is 2 160 m long with volume of about 240 thousand m3. The paper analyzes the principle, lectotype, setting, workflow and construction of the steel box girder dehumidification. And the paper protocols the quality inspection and evaluation standards of the steel box girder dehumidification in Taizhou Bridge. It proposes reference for similar project.
A systematic description of the design of health monitoring system for the structure of extra-large suspension bridge is presented based on Taizhou Bridge. The system consists of 3 sub-systems of sensors, data acquisition and transmission, and data processing and analysis. It merges the traditional wire acquisition method and the new wireless acquisition method, which is the first large-scale application in China as well as in the world.
The total quantity of concrete exceeds 30 000 m3 for the north anchor caisson of Taizhou Bridge, which is the largest quantity underwater concrete for bottom sealing construction till now in China, and its construction is quite difficult with high requirements for site organization. This article presents the bottom sealing construction technology for the caisson of north anchor of Taizhou Bridge mainly in the aspects of base cleaning, bottom sealing equipment arrangement and sealing concrete construction technique.
The middle tower of Taizhou Bridge consists of deepwater caisson foundation and steel tower with herringbone shape along the longitudinal direction. The construction is complex. Based on previous study, using the technology of up-stream and down-stream anchor pier positioning and the system of information real-time monitoring ensures position and implantation. Meanwhile，control measure is used to prevent caisson sinking suddenly and extra-sinking in final stage. Erection accuracy of steel tower is very high, but adjusted segments are few. During the construction, the structure system changes frequently. To the feature, the method of whole process control based on geometric control is used in the project, which analyzed the error of manufacturing segment, linear of pre-assembled segment and erection, and accuracy management system is established uniformly. The final accuracy of erection is better than that designed. Many innovative technologies are obtained in this project, and the key technologies about construction of deepwater caisson , manufacturing and erection of steel tower are formed, which can be referred for other similar projects in the future.
The middle tower of Taizhou Bridge is a steel frame with longitudinal herringbone shape and lateral gate shape, which is used for the first time. The technology with segments fabricated in the factory and erection at site is used in the construction of the middle steel tower. A full-procedure construction control system to the complicated tower is set up. Based on precise monitoring and control to the shape of the segments and the line-shape of the tower at the fabrication stage, the adjustment of the adjusting gap of the tower is calculated according to the actual error of the tower at the erection stage, and the line-shape error of the tower is adjusted. The result of the implementation of the middle steel tower of Taizhou Bridge indicated that the line-shape control method adapted could be effective, and the precision of final line-shape of the middle steel tower is better than that of the design requirements.
cat-walk is the most important passage and place for working at high altitude in the construction of suspension bridge superstructure, and its profile, structural safety and anti-wind stability are related to the quality, progress and work safety of all main work sections in the construction of the whole superstructure. The load bearing cables are the main load-bearing components in cat-walk structure, usually made of twisted steel wires. In the construction of superstructure of Taizhou Bridge, for the cat-walk load bearing cable wire ropes for repeated use, complete inspection plan is formulated with reference to relevant specification in China, with good effect in ensuring the structural safety of constructing cat-walk and lowering construction cost, and this is of positive significance to the repeated use of cat-walk wire ropes in bridge construction in China.
For the large number of wire strands and the long distance of strand traction, the wire strands are erected normally with gantry pulling traction system that allows continuous pylon passing in the construction of main cables with PPWS(prefabricated parrel wire strand) method for an extra-large span suspension bridge. The accurate calculation of traction force is of realistic significance to the selection of traction equipment and ensuring smooth construction. In early days of suspension bridge construction, the capacity demand and type of traction equipment were determined mainly based on experience. In this article, exploration was made for the traction force calculation method of the gantry pulling traction system for PPWS construction, and the results were compared with measured data on work site. It proves that the calculation result is reliable and can be used in construction calculation.
Taizhou Bridge is the first three-tower two-span suspension bridge with spans over 1 000 m in the world. Its main spans are 2×1 080 m; the middle tower is a steel frame with longitudinal herringbone shape and lateral gate shape; the side towers are gate shaped concrete frames; the stiff girder consists of flat streamline steel box girders, with a total of 136 steel box girders of about 33 426 t for the whole bridge. This article determines the proper lifting sequence of steel box girders of this threetower suspension bridge by analyzing the effect of steel box girders lifting sequence on structural system and difficulty in construction .
In this paper, Taizhou Bridge, a three-tower suspension bridge was investigated to discover the flutter stability of deck under symmetrical construction through FEM（finite element method） analysis and full aeroelastic model tests. The assessment of flutter stability during deck construction stage was performed based on analysis of the monthly maximum wind speed in the past 30 years. In the end, the assessment and management strategy of flutter stability were proposed, which can be referred for other bridges.
Three different models are discussed in this paper, which are consolidation single tower model with body flexibility considered, linear single tower model based on m analysis method and nonlinear single tower model based on p-y curve analysis method, respectively. Seismic responses of these models are analyzed under ground motion inputs of El-Centro Earthquake and Kobe Earthquake and the calculation results are compared in this paper. The result turns out that the simulation method of linear single tower model of open caisson based on m analysis method produces larger structual response than that of the nonlinear single tower model based on p-y curve analysis method. While the simulation method of linear single tower model of pile group foundation based on m analysis method matches very well with that of nonlinear single tower method based on py curve analysis method.
The foundation of the middle pylon of Taizhou Bridge is located above the overlying deposit with the height of 200 m in the water. The round rectangular caisson foundation with the plane dimension of 58 m×44 m and the height of 76 m is employed. To verify the safety and stability of the middle pylon of Taizhou Bridge, a physics model with the scale of 1∶100 to the real structure is built up. The ultimate bearing capacity of the caisson foundation and the influence of sinking depth, soil moisture content, and the side wall friction on the bearing capacity are obtained.
The foundation of the gravity anchorage is usually simplified as shallow foundation, which is diseconomy when the depth effect is neglected. Because the embedded depth of caisson foundation south anchorage of Taizhou Bridge is 42 m, FEM(finite element method) is utilized to research the depth effect of the caisson foundation in the stability computing. It is clear that the depth effect improves the bearing capacity of anchorage foundation dramatically by comparing the variation of the displacement and the rotation angle of the anchorage foundation in the periods of construction and operation.
Compared to the tower of common twospan suspension bridges, the middle towers of multispan suspension bridges have several different characteristics, such as the constraints, service conditions and loads, etc, which affect the safety and applicability of the bridges. In this paper, a small-scale model was designed for the middle tower of Taizhou Bridge, based on its actual working conditions. By the finite element method, the similarities between the experiment and the prototype were investigated from three aspects, including the internal forces, displacements and strains. It is demonstrated from the investigation that, with the geometric size and material modulus as the essential parameters, the designed model herein can satisfy the requirements of mechanical properties of experiment.
In this paper, the basic model of main cable slip between saddles is established. Three methods to assess the safety of saddle sliding on middle tower of the Taizhou Bridge are presented based on this model. The first assessment method is deterministic, which is based on live load model of design codes. Several design codes models are used, and assessment results are compared. In the second method, the uncertainty of traffic load is considered in a more accurate way. Random traffic flow simulation model is developed to simulate real traffic situation on the bridge. Extreme value of unbalance force is obtained by extrapolation methods based on Rice formula. The last assessment method is probabilistic based method.The probabilistic model of load effect and structure resistance is established, and reliability index of anti-sliding safety is calculated. All three assessment results indicate that the middle tower saddle of the Taizhou Yangtze River Bridge is safe and reliable.
Taizhou Bridge is the first kilometer level threetower and twospan suspension bridge in the world. The three-dimensional fullbridge FEM (finite element method) model of the Taizhou Bridge and the random vehicle loading on the bridge finite element model by simplified vehicle load model are established. The vertical displacement and bending moment values are calculated to analyze the position of the maximum stress for the steel box girder under vehicle load. Then the critical position can be determined to carry out fatigue analysis for the steel box girder.
Taking Taizhou Bridge for example, dynamic characteristics of the finite element model are analyzed and then the effects of different moving speeds and loads on dynamic response of three-tower twospan suspension bridge are studied. The result demonstrates that vertical bending of natural frequency is approximately 0.08 Hz, which is far below natural frequency loading truck, and will not form resonance condition. The response of force and displacement of three-tower twospan continuous suspension bridge under simply moving loads and equivalent static loads are the same. The structural will be greater when moving loads quantity and speed become greater and they have similar positive relationship. However, the load amplification factor of structural force and displacement does not vary with the quantity change of moving loads.
The paper presents the traffic volume and loading of Yangtze River bridges in Jiangsu Province from 2007 to 2010. The results show that traffic volume is increasing along with the time. The traffic volume and loading of truck of Yangtze River Bridge are analyzed by wheel load spectrum. The paper gives the truck wheel load and typical wheel load ratio in Jiangsu Province. The overloading analysis show that overloading is serious in Yangtze River Bridges in Jiangsu Province.The research results is useful to the steel deck pavement design of Taizhou Bridge.
Based on the mechanism of strength, the reserved time and curing temperature of epoxy asphalt mixture are studied as the influencing factors of strength, and the range of reserved time and the strength increasing law of epoxy asphalt mixture in different temperatures are determined. Then dynamic differential scanning calorimeter (DSC) curve of epoxy asphalt mixture at different heating rates is measured using DSC. We use the method of nonlinear regression to obtain the key parameters of curing kinetics. Then the model of curing reaction of epoxy asphalt binder is established. The results can guide the production and construction of epoxy asphalt mixture. Meantime, it also can provide reference value on when to open the paving layer to traffic.
In order to reflect the synergistic effect and working environment of the long-span steel bridge deck-pavement system truly in laboratory experiments, this paper studies the synergistic experimental model of flexible long-span steel bridge deck-pavement system. Firstly, the local box girder FEM(finite element method) model considering the whole bridge deformation is established. And the deck pavement's stress and strain are analyzed. The entire bridge effect parameter is 1.17. Then, the synergistic experimental model is established.Taking the maximum stress and strain value of local beam section as reference value, the related structure parameters of early model scheme are revised. On this basis, to ensure the consistency of designing for the synergy model and the prototype, stress value of the revised test model and local beam section model in the control point is compared. Eventually, the synergistic experimental model of long-span steel bridge deck-pavement system is obtained in this paper. The results may provide theoretical basis for designing of laboratory experiment model on steel bridge deck.
Special programs and general programs applied to suspension bridge analysis have their limitations. This paper focuses on ANSYS-secondary-development and makes it possible to analyze suspension bridges both with accuracy of special programs and convenience of general programs. This paper is dedicated to saddle simulation,incremental launching realization and how to obtain unstressed length of main cable and slings and how to keep it unchanged. In the end, the method is verified through finite element model in Runyang Yangtze River Bridge.
According to the phenomenon of laminating crack while tensioning the pre-stressed cables at bottom slab in closure segment for prestressed concrete continuous box girder bridges constructed by hanging basket, different failure criterions of concrete are introduced in this paper. It indicates from theory that the failure criteria under biaxial stress is more applicable to anti-crack design than the maximum tensile stress criterion for closure segment of box girder bridges. Based on 8 typical bridges that selected as the research objects, the FEM (finite element method)models are established and the transverse and vertical stress between pre-stressed tendons at bottom slab in closure segment are obtained; the stress state and security of bottom slab under different failure criteria are forecasted and compared with field test data. Finally, the theoretical analysis is proved. The conclusions can be regarded as reference for the anti-crack design of similar bridges.