Study on Structures of Ultra-high-performance Concrete-filled Steel Tubular Bridge
To promote the application of rectangular ultra-high-performance concrete-filled steel tubular(UCFST)composite structures,and promote the development of lightweight and assembly technology of bridge structures,the design and study were conducted on medium span through type UCFST bridges based on a certain overpass project of Shanghai-Wuhan expressway.It is proposed to use ultra-high performance steel-concrete composite structures as the main load-bearing components of bridge.That has excellent performances(e.g.,high bearing capacity,high durability,convenient construction,and high degree of assembly),which meet the current development needs for lightweight and thin-walled bridge construction.Based on the engineering construction conditions,3 design bridge type were proposed,which were the composite truss bridge,tied arch bridge,and cable-stayed bridge.The bridge design innovatively adopted the CFRP suspender,CFRP prestressed reinforcement and cold-formed crimped U-shaped beam with UHPC bridge deck structure.The strength,stiffness,stability and dynamic characteristics of each design structure were analyzed by using finite element model.The design results met the requirements of the specification.The technical and economic analysis on each bridge type was carried out to provide a reference for the design of medium span overpass bridges,and the application of new materials(e.g.,UHPC and CFRP).The result indicates that for the simple supporting composite truss girder,the dynamic characteristic is better,and the stiffness and stability are moderate.For the continuous composite truss girder,the strength is relatively balanced,and the material utilization rate is relatively high,but the vertical stiffness is relatively small.For the tied arch bridge,the vertical stiffness is relatively large,but the lateral stability is relatively poor.For the cable-stayed plate bridge,the vertical stiffness is relatively large,and the lateral stability is relatively good.Moreover,under the same conditions,the material-cost ratio of simple supporting truss,tied arch bridge,continuous truss girder and cable-stayed bridge is 1∶1.02∶0.97∶1.83.Therefore,the economy of continuous composite truss is the best,while that of cable-stayed plate bridge is relatively poor.The construction performance of composite truss bridge is better,and the landscape effect of tied arch bridge and the cable-stayed plate bridge is more prominent.
NETL
NSTL
万方数据
