基于PLAXIS的新旧路基结合部台阶开挖方案的有限元分析

在旧路加宽改造过程中,新旧路基结合部容易产生较大的差异变形,导致路面结构的破坏,并降低路堤的稳定性。为了减小结合部的工后差异沉降,运用PLAXIS有限元软件对旧路加宽施工过程中台阶的开挖方案进行数值模拟分析,计算各种开挖方案下新旧路基的差异沉降,提出合理的施工方案。计算结果表明:卸载及加载量越大,新、旧路基在结合部的横向和竖向差异变形也越大,旧路加宽改造时优先选用方式2和方式4这两种台阶开挖方式。

Finite Element Analysis on Schemes of Steps Excavation in Old and New Subgrade Junction Based on PLAXIS

In the course of old road reform and widen,the junction between old and new subgrade prones to large differences in deformation,which may lead to the destruction of the pavement structure and stability reducing of the embankment.In order to reduce the differential settlement of the junction after the construction process,finite element software PLAXIS was used to simulate and analyze the schemes of excavation about steps during the construction process of old road widening.The different settlements between old and new embankment under all kinds of excavation schemes were calculated,and a reasonable construction scheme was proposed.The calculated results show that,with the greater of unloading and loading amount,the different deformations at the junction in both horizontal and vertical directions will be greater.Scheme 2 and 4 should be used in priority in the course of reforming and widening the old road.