钢管砼桁拱静力性能分析

以福建闽清净跨１３６ｍ的石潭溪钢管砼桁为分析对象，进行了施工中和成桥后的静力测试和计算分析．结果表明，横撑对荷载横向分布起二次分配作用，能降低偏载时单肋拱面内受力；全焊式桁肋胶管中的弯矩值较小．可以按理想桁格式考虑；钢管初应力对钢管砼构件承载力的影响不大，使用阶段钢管对核心砼的紧箍力已发挥作用；仅靠空钢管无论是承载力还是变形都不能满足设计要求．

The Static Property Analysis of CFST Truss-Rib Arch Bridge

The concrete-filled-steel-tube(CFST truss arch or Shitanxi Bridge in Minqing, Fujian Province, with a clear span of 136 metres, is taken as an object for the analysis of static test and calculation during and after the bridge is built and open to traffic. The analysis results show that: cross-support takes effect of second distribution to loads, which can reduce arch rib's inner-force while bearing loads; the value or the momen of full-weld truss rib's minor tube is relatively small, so it can be considered as perfect truss; the influence of steel-tube's initial stress to CFST elements' bearing capacity is not big; but during the service period, the inhibition force of steel tube to inner concrete will begin to take effect; therefore neither bearing capacity nor deformation can meet the requirements of the design with only hollow steel tubes.