高速公路扩建工程中新路填筑对老路影响的参数分析

Parameter Analysis of the Influence of the Construction of New Embankment on the Old Embankment in the Widening of Expressway

道路扩建中加宽路堤的填筑将会改变原有路堤及地基的应力场和应变场,引起老路的附加差异变形。采用弹塑性有限元参数分析方法探讨了不同加宽路堤宽度、不同软土层厚度、不同的新老路堤刚度比时加宽路堤的填筑对老路变形规律的影响。计算结果表明:拓宽路堤的填筑将会引起老路不同位置的过大附加差异沉降,导致路面横坡比改变值超过路面结构的容许值,从而引起路面结构性破坏和路面服务性能的降低。因此,必须采用合适的软基处理方案对加宽部分软基进行处理。

The finite element technique using Mohr-Coulomb elastic-plastic soil behavior model is applied to analysis of the influence of the new embankment construction on the old embankment in the widening of expressway embankments on soft foundation soils. The calculation results indicate that the construction of new embankment induces unacceptable differential settlement between the center and the shoulder of old embankment, then pavement cracking usually occurs and the grade of highway is decreased. Right treatment techniques should be taken to reduce the influence of the widening on the old embankment.