桁式组合拱桥存在的问题及加固新思路的探讨

从结构整体性、强度计算方法、内力调整方面查找桁式组合拱桥存在问题的根源,指出危旧桁式组合拱应采用按施工阶段来划分不同工况的应力叠加计算方法来评估其承载力.建立了一个工程实例的有限元模型,进行了分析验证.对比桁和拱在不同阶段的受力特性,依据斜杆在不同阶段内力的变化,然后提出一个由可调内力的柔性拉索来置换不可调内力的刚性斜杆的加固新思路.用实例验证了理论上的可行性.

Research on the Problems in Hybrid Truss Arch Bridge and Its Reinforcement Scheme

The sources of problems for the pre-stressed concrete hybrid truss arch bridge are discussed.The shortage of construction connection,intensity analysis method and internal force adjusting are revealed.The stress superposition method is adapted to evaluate the bearing capacity of the old and dangerous hybrid truss arch that is divided into several construction stages.A finite element model is set up and verified by an example.The characters of the truss and arch are compared.According to variety of internal force of the inclined bar,a reinforcement scheme that the inclined bar is replaced by the cable is also advanced.Its theoretic feasibility is verified.