格栅加筋处治沿海高速公路拓宽路堤数值分析

Numerical analysis of geogrids reinforcement for widening embankment of coastal freeway

为了研究沿海高速公路路堤拓宽差异沉降关键影响因素,采用有限差分软件FLAC^(3D)建模分析,探讨土工格栅加筋参数(格栅层数与格栅弹性模量)、新路堤填土参数(土体重度与土体弹性模量)对拓宽路堤差异沉降的影响,并提出了路堤拓宽最优设计方案。结果表明:土工格栅加筋参数对路堤差异沉降改善作用较小,而新旧路堤差异沉降随着路堤填土重度的增大而增大,且随着路堤填土弹性模量的增大而减小;最后,通过对影响拓宽路堤差异沉降的关键影响因素和拓宽路堤最大剪应变增量进行分析,建议在实际改扩建路堤加宽过程中选择轻质高强的路堤填料,以此来改善路堤拓宽差异沉降的影响。

In order to study the key influencing factors of differential settlement of embankment widening of coastal expressway,the finite difference software FLAC^(3D) was used to model and analyze the influence of geogrid reinforcement parameters(geogrid layer number and geogrid elastic modulus)and new embankment filling parameters(soil weight and soil elastic modulus)on differential settlement of widening embankment,and the optimal design scheme of embankment widening was proposed.The results show that the geogrid reinforcement parameters have little effect on the improvement of differential settlement of embankment,and the differential settlement of new and old embankments increases with the increase of embankment filling weight,and decreases with the increase of embankment filling elastic modulus.Finally,through the analysis of the key influencing factors affecting the differential settlement of the widened embankment,combined with the analysis of the maximum shear strain increment of the widened embankment,it is suggested that the lightweight and high-strength embankment filler should be selected in the actual widening process of the widening embankment to improve the influence of the differential settlement of the widening embankment.