曲线石拱桥加宽改造中桥面结构有限元分析

Finite element analysis on bridge deck structure during the widening modification of curved stone arch bridge

本文以湖北省五峰土家族自治县境内某座曲线石拱桥加宽改造项目为例,采用有限元软件Midas FEA建立桥面结构的空间实体模型,对比分析不同活载工况下的桥面结构变形和应力,同时对最不利受力工况下的桥面结构进行非线性分析。结果表明:桥面结构的最不利受力位置为悬挑梁跨中截面下缘和石拱桥侧墙支承位置的桥面板上缘;石拱桥在加宽改造过程中需严格控制拱上填料的施工质量,防止桥面板、悬挑梁与拱上填料脱空;为避免拱上填料产生过大的固结沉降,建议换填轻质填料,并对填料进行压浆处理。

The widening modification project of a curved stone arch bridge in Wufeng Tujia Autonomous County,Hubei Province,is taken a san example,the finite element software Midas FEA is used to establish the spatial solid model of the bridge deck structure,and the deformation and stress of the bridge deck structure under different live load working conditions are compared and analyzed.At the same time,the bridge deck structure under the most unfavorable working conditions is analyzed by the nonlinear analysis method.The results show that the most unfavorable stress position of the bridge deck structure is the lower edge of the mid-span section of the cantilever beam and the upper edge of the bridge deck at the supporting position of the side wall of the stone arch bridge.In the process of widening modification of stone arch bridges,the construction quality of the filler on the arch must be strictly controlled to prevent the bridge deck,cantilever beam and the filler on the arch from being void.In order to avoid excessive consolidation settlement of the filler on the arch,it is recommended to replace the light filler and to grout the filler.