新建铁路桥下穿既有铁路桥交叉基础影响分析

Influence of Crossing Foundation of Existing Bridges Under New Railway Bridge

为研究新建铁路桥在交汇区域内对既有桥梁桩基础的影响,利用ABAQUS有限元软件建立交叉区域内土体与桩基的三维模型.分析了新建铁路桥在施工与运营阶段中桥址区土体位移、既有铁路桥桩基础位移和应力变化趋势,发现各阶段既有铁路桥桩基特性的变化趋势相同,且在新建铁路桥运营中既有桥梁基础特性的变化相对较大.说明在铁路桥的设计施工时,应验算该桥梁运营阶段时周围既有桥梁的基础特性变化,确保变化值在许可范围之内.

In order to study the influence of the newly built railway bridge on the existing bridge pile foundation in the intersection area,the three-dimensional model of the soil and pile foundation in the intersection area was established by using ABAQUS finite element software.The displacement of the soil in the middle bridge site area and the variation trend of the displacement and stress of the bridge foundation of the railway were studied.It is found that the characteristics of the pile foundation characteristics of the railway bridge are the same at each stage,and the changes in the basic characteristics of the bridge are relatively large in the operation of the newly built railway bridge.It is indicated that during the design and construction of the newly built railway bridge,the basic characteristics of the existing bridges around the bridge operation phase should be checked to ensure that the change value is within the permitted range.