单主缆悬索桥钢箱梁顶推过程结构力学性能分析

摘要

某单主缆地锚式悬索桥加劲钢箱梁采用多点多台步履式顶推施工方案，在顶推过程中，钢箱梁、导梁和临时支墩的变形和受力变化，以及墩顶支撑位置处钢箱梁的局部应力情况应予关注，避免因钢箱梁底板发生局部屈服而影响结构安全和后续顶推工作。文中通过运用有限元软件分别进行整体和局部模拟计算分析，对顶推施工进行合理地指导。监测结果表明，顶推过程中钢箱梁顶推线形与理论计算线形吻合较好，临时结构未出现失稳状况。%The construction technology for a single main cable suspension bridge is that the stiffened steel box girder is multi-point and multi-stage walking style launched.In the process of incremental launching,in order to avoid the steel box girder bottom partial yield with the result of affecting struc-tural safety and subsequent pushing construction technology,the problems should be paid attention to,including the deformation and stress change in the steel box girder,the nose girder and the tempo-rary support pier as well as the local stress in the steel box girder which located on the supported pier. For scientific and effective guiding the launch construction,global and local simulation calculations are respectively analyzed by finite element software.Monitor results show that:the steel box girder bridge alignment agrees well with the designed alignment and instability does not happen to the tem-porary structure during the construction.