土工格室柔性搭板处治的路桥过渡段差异沉降三维数值分析

Three-dimensional Numerical Analysis of Geocell Flexible Approach Slab for Treating Differential Settlement at Bridge-subgrade Transition Section

应用MARC软件,建立路桥过渡段差异沉降的三维计算模型。基于该模型及不同的地基沉降模式,分别对土工格室加筋体和柔性搭板消化地基沉降、协调和控制桥头差异沉降的作用机理及其对地基沉降的适应性进行了三维数值仿真分析。结果表明:土工格室复合体限制了周围土体的侧向变形,减小了路堤本身的压缩变形;同时,土工格室柔性搭板能有效地阻止上层土体向下沉降,减小路基竖向应力,使得桥台与路堤之间的沉降差在较广的范围内得到平缓过渡。

Applying for MARC software, three-dimensional numerical model of differential settlement at bridge-subgrade transition section was built. Based on the model and different foundation settlement mode, the active mechanism of geocell reinforced body and flexible approach slab for assimilating the foundation settlement, coordinating and controlling the differential settlement at the bridge-subgrade transition section and its adaptability to foundation settlement were studied by three-dimensional numerical simulation. The results show that the lateral distortion of surrounding soil is restricted and the compaction distortion of embankment decreases because of existence of geocell composite body. Due to existence of geocell flexible approach slab, the settlement of upper filling is prevented effectively and the vertical stress in subgrade decreases, so the settlement difference between the abutment and embankment is transited smoothly at the longer section.