高大扶壁式挡土墙墙后土压力特性有限元分析

Analysis of Behaviors of Earth Pressure Behind Counterfort Retaining Wall with Finite Element Method

对扶壁式挡土墙进行三维有限元分析,得到了立板后的土压力分布,结果表明:竖向土压力分布先随覆土深度的增加而增大,但到一定深度后,随覆盖土层厚度的增加土压力增大率减小,当覆盖土层厚度增大到一定数值后,土压力几乎不再增大;水平方向的土压力分布受肋板的直接影响,在立板的上部,受肋板的影响较小,土压力分布较为均匀,在立板的下部,受到肋板的影响较大,表现出中部大,两侧小,呈类似“抛物线”型分布,深度越大,这种现象越明显,“抛物线”越集中。

With the 3D FEM analysis of a counterfort retaining wall, the distribution of earth pressure behind the vertical wall is obtained. The calculated results show that the vertical distribution of earth pressure increases firstly with the depth of soil mantle, but the rate of increase of the earth pressure reduces with the increase of the depth of soil mantle when it comes to a certain depth. When the depth of soil mantle increases to a certain amount, the earth pressure increases almost no more. The horizontal distribution of earth pressure is directly influenced by costal plates. At the top of the vertical wall, the horizontal earth pressure is less influenced by the costal plates and the earth pressure is more homogeneously distributed,while at the low part of the vertical wall ,the horizontal earth pressure is more greatly influenced by the costal plates and the earth pressure is distributed like a ＂parabola＂ with the middle portion being large and the two ends being small. The deeper the soil mantle goes, the more evident the phenomenon is and the more concentrated the ＂parabola＂ gets.