新建公路对下穿既有高铁桥墩变形的影响研究

针对新建公路距高铁桥墩过近、高铁桥墩边坡偏压等问题，以襄垣县北二环下穿太焦高铁浊漳河北底特大桥项目为依托，采用边坡挖除整平、设置挡土墙等工程防护措施，并对工程全周期进行三维有限元数值模拟计算，分析了该项目在复杂工程条件下高铁桥墩的变形机制。结果表明:工程结构间距离越近，互相影响越大。挖除换填造成偏压的土体和设置挡墙可以使位移变形量降低60 %～90 %，既有铁路桥墩的位移变形量得到有效控制。

Research on Deformation Impact of New Highway underneath Passing Existing High-speed Rail Bridge Pier

In view of issues such as newly built highway is too close to high-speed railway bridge pier and unsymmetrical pressure of high-speed railway bridge pier side slope, based on the north second ring road of Xiangyuan county underneath passing the super large bridge on the north side of Zhuozhang river of the Taijiao (Taiyuan—Jiaozuo) high-speed rail project, engineering protection measures such as slope excavation leveling and retaining wall have been adopted and project lifecycle three dimensional finite element numerical simulation has been conducted to analyze the high-speed railway bridge pier deformation mechanism under complex engineering conditions. The results show that closer the construction structures is, the greater the mutual influence is. The displacement and deformation of removal and bias of the soil mass caused by replacement and filling and setting up retaining wall can be reduced by 60 % ~ 90 %, and the displacement and deformation of the existing railway bridge piers can be effectively controlled.