大跨度变截面连续箱梁悬臂挂篮施工转支架现浇关键设计及结构验算

Key Design and Structural Checking of Cast-in-place Support for Cantilever Hanging Basket Construction of Large-span Variable Cross-section Continuous Box Girder

悬臂挂篮施工作为大跨度变截面连续箱梁常用的施工方法,被广泛应用于高速公路、铁路桥梁中。但其施工工期较长,且对施工空间有一定要求,部分项目仍有变更为大节段现浇的需求。文章以某(40+60+40)m变截面连续箱梁为例,详细说明了变更施工方案后的构造该如何重新设计,并分析了两种施工方案的结构受力差异,以期为同类桥梁变更提供参考。

As a common construction method of long-span variable cross-section continuous box girder,cantilever hanging basket construction is widely used in highway and railway bridges.However,its construction period is long,and there are certain requirements for construction space.Some projects still need to be changed to large-segment castin-place.Taking a(40+60+40)m variable cross-section continuous box girder as an example,this paper explains in detail how to redesign the structure after changing the construction scheme,and analyzes the structural stress difference between the two construction schemes.It is hoped that this study will provide reference for similar bridge changes.