Mechanical behavior of concrete slab of large-span through tied-arch composite bridge was investigated by finite element analysis (FEA). Improved methods to decrease concrete stresses were discussed based on compariso...Mechanical behavior of concrete slab of large-span through tied-arch composite bridge was investigated by finite element analysis (FEA). Improved methods to decrease concrete stresses were discussed based on comparisons of different deck schemes, construction sequences and measures, and ratios of reinforcement. The results show that the mechanical behavior of concrete slab gets worse with the increase of composite regions between steel beams and concrete slab. The deck scheme with the minimum composite region is recommended on condition that both strength and stiffness of the bridge meet design demands under service loads. Adopting in-situ-place construction method, concrete is suggested to be cast after removing the full-supported frameworks under the bridge. Thus, the axial tensile force of concrete slab caused by the first stage dead load is eliminated. Preloading the bridge before concrete casting and removing the load after the concrete reaching its design strength, the stresses of concrete slab caused by the second stage dead load and live load are further reduced or even eliminated. At last, with a high ratio of reinforcement more than 3%, the concrete stresses decrease obviously.展开更多
When the installation of cables and pipelines needs to go across rivers,bridges are usually adopted to support the cables and pipelines for crossing the rivers.The measure can make full use of the space resources and ...When the installation of cables and pipelines needs to go across rivers,bridges are usually adopted to support the cables and pipelines for crossing the rivers.The measure can make full use of the space resources and have no effect on the flow pattern of rivers.For this reason,analysis on the structural-type design of a large-span steel truss bridge specially used for cables has been performed.The numerical results indicate that the stayed-cable bridge with steel truss beam and concrete main tower has better performance and improved structural type caparisoned with that of the beam and arch bridges,and the construction of the major beam can be without the temporary support.展开更多
Based on the capacity/demand(C/D)analysis of bridge components,and life cycle and performance based seismic design principles,a practical approach is developed for the seismic performance evaluation of super-long span...Based on the capacity/demand(C/D)analysis of bridge components,and life cycle and performance based seismic design principles,a practical approach is developed for the seismic performance evaluation of super-long span cable-stayed bridges.According to the approach,the seismic performance evaluation of the Sutong Bridge,which is a cable-stayed bridge with a main span of 1 088 m,is completed,and the practicality of the approach is validated.The earthquake resistance level for super-long span cable-stayed bridges is discussed,including the earthquake level,its corresponding structural performance and check indices.And a set of formula for capacity/demand ratio calculation of bridge components is proposed.展开更多
Cable-stayed bridge is a kind of bridge under bending pressure and tension of supporting system. The main stressed component of this kind of bridge is stay cable, which plays a vital role in the whole bridge structure...Cable-stayed bridge is a kind of bridge under bending pressure and tension of supporting system. The main stressed component of this kind of bridge is stay cable, which plays a vital role in the whole bridge structure. Based on this, this paper takes the D1 cable-stayed bridge project of Malaysia Coastal Avenue as an example to deeply explore the construction technology of parallel steel cable stayed cables of long-span cable-stayed bridges, aiming at providing scientific construction technology support for the construction of cable-stayed bridges and ensuring the quality of bridge construction.展开更多
The main bridge of the North Branch Bridge of Qidu Bridge is a double-tower central cable-stayed bridge with composite beams with a main span of 360m m. The main tower is a circular single-column tower with a tower he...The main bridge of the North Branch Bridge of Qidu Bridge is a double-tower central cable-stayed bridge with composite beams with a main span of 360m m. The main tower is a circular single-column tower with a tower height of 118.6m m. Based on the site and the structural characteristics of the main tower, one tower crane is used as the vertical lifting equipment and one elevator is used as the personnel access, the lower tower column is constructed by turning over the formwork, and the middle and upper tower columns are constructed by hydraulic climbing formwork. The successful application of this construction technology provides reference and guidance for similar projects in the future.展开更多
Changqing Yellow River Super-long Bridge of Zhengzhou-Ji'nan HSR is a partial cable-stayed bridge with concrete main girder and a unit length of 1,080 m.Studies are carried out on the key technologies of bridge de...Changqing Yellow River Super-long Bridge of Zhengzhou-Ji'nan HSR is a partial cable-stayed bridge with concrete main girder and a unit length of 1,080 m.Studies are carried out on the key technologies of bridge design,and the main conclusions are as follows:The whole unit adopts the supporting system of tower pier consolidation and tower-beam separation,and each pier is provided with seismic mitigation and isolation bearing;shaped-steel reinforced concrete bridge tower is adopted to bring into full play the tensile performance of steel and the compressive performance of concrete,and avoid the construction challenges of setting up multi-layer and multi-stirrup reinforcement while improving the bearing capacity of section;a new type of double-side and bi-directional anti-skid anchorage device is adopted for the cable saddle of wire divider pipe in order to withstand the unbalanced cable force,and verify the reliability of the anti-skid anchorage device by solid model test;and large-segment cantilever pouring design is adopted for the main girder with a maximum segment length of 8 m to effectively shorten the construction period of the bridge.展开更多
基金Project(2005k002-c-2) supported by the Science and Technology Development Program of Railways Department, China
文摘Mechanical behavior of concrete slab of large-span through tied-arch composite bridge was investigated by finite element analysis (FEA). Improved methods to decrease concrete stresses were discussed based on comparisons of different deck schemes, construction sequences and measures, and ratios of reinforcement. The results show that the mechanical behavior of concrete slab gets worse with the increase of composite regions between steel beams and concrete slab. The deck scheme with the minimum composite region is recommended on condition that both strength and stiffness of the bridge meet design demands under service loads. Adopting in-situ-place construction method, concrete is suggested to be cast after removing the full-supported frameworks under the bridge. Thus, the axial tensile force of concrete slab caused by the first stage dead load is eliminated. Preloading the bridge before concrete casting and removing the load after the concrete reaching its design strength, the stresses of concrete slab caused by the second stage dead load and live load are further reduced or even eliminated. At last, with a high ratio of reinforcement more than 3%, the concrete stresses decrease obviously.
文摘When the installation of cables and pipelines needs to go across rivers,bridges are usually adopted to support the cables and pipelines for crossing the rivers.The measure can make full use of the space resources and have no effect on the flow pattern of rivers.For this reason,analysis on the structural-type design of a large-span steel truss bridge specially used for cables has been performed.The numerical results indicate that the stayed-cable bridge with steel truss beam and concrete main tower has better performance and improved structural type caparisoned with that of the beam and arch bridges,and the construction of the major beam can be without the temporary support.
基金National Key Technologies R&D Program(No.2006BAG04B01),research on technical standards,key structures and their characteristics of kilometer-magnitude cable-stayed bridges
文摘Based on the capacity/demand(C/D)analysis of bridge components,and life cycle and performance based seismic design principles,a practical approach is developed for the seismic performance evaluation of super-long span cable-stayed bridges.According to the approach,the seismic performance evaluation of the Sutong Bridge,which is a cable-stayed bridge with a main span of 1 088 m,is completed,and the practicality of the approach is validated.The earthquake resistance level for super-long span cable-stayed bridges is discussed,including the earthquake level,its corresponding structural performance and check indices.And a set of formula for capacity/demand ratio calculation of bridge components is proposed.
文摘Cable-stayed bridge is a kind of bridge under bending pressure and tension of supporting system. The main stressed component of this kind of bridge is stay cable, which plays a vital role in the whole bridge structure. Based on this, this paper takes the D1 cable-stayed bridge project of Malaysia Coastal Avenue as an example to deeply explore the construction technology of parallel steel cable stayed cables of long-span cable-stayed bridges, aiming at providing scientific construction technology support for the construction of cable-stayed bridges and ensuring the quality of bridge construction.
文摘The main bridge of the North Branch Bridge of Qidu Bridge is a double-tower central cable-stayed bridge with composite beams with a main span of 360m m. The main tower is a circular single-column tower with a tower height of 118.6m m. Based on the site and the structural characteristics of the main tower, one tower crane is used as the vertical lifting equipment and one elevator is used as the personnel access, the lower tower column is constructed by turning over the formwork, and the middle and upper tower columns are constructed by hydraulic climbing formwork. The successful application of this construction technology provides reference and guidance for similar projects in the future.
文摘Changqing Yellow River Super-long Bridge of Zhengzhou-Ji'nan HSR is a partial cable-stayed bridge with concrete main girder and a unit length of 1,080 m.Studies are carried out on the key technologies of bridge design,and the main conclusions are as follows:The whole unit adopts the supporting system of tower pier consolidation and tower-beam separation,and each pier is provided with seismic mitigation and isolation bearing;shaped-steel reinforced concrete bridge tower is adopted to bring into full play the tensile performance of steel and the compressive performance of concrete,and avoid the construction challenges of setting up multi-layer and multi-stirrup reinforcement while improving the bearing capacity of section;a new type of double-side and bi-directional anti-skid anchorage device is adopted for the cable saddle of wire divider pipe in order to withstand the unbalanced cable force,and verify the reliability of the anti-skid anchorage device by solid model test;and large-segment cantilever pouring design is adopted for the main girder with a maximum segment length of 8 m to effectively shorten the construction period of the bridge.
