加筋土高挡墙三维变形分析

3D Numerical Simulation of the Deformation of Reinforced Earth Retaining Wall

加筋土挡墙在复杂地形下的三维结构特性往往对其变形和稳定影响较大。将加筋土看作复合材料,对某机场高边坡挡墙未加筋与加筋土状态下土体进行了大三轴试验,并合理选取了计算参数,使用Mohr-coulomb弹塑性模型进行了未加筋与加筋挡墙的三维数值分析,研究发现:①挡墙变形受地形影响明显,有效应力随着挡墙高度的增加而增加,以墙高最大断面处应力最大;同一高程处有效应力最大值发生在挡墙后填土部分;挡墙沉降在谷地及较陡的山体处较大;②加筋对水平位移影响较大,与未加筋状态相比加筋后最大水平位移减少约45%;③随挡墙填筑高度的增加,水平位移初期快速增大,之后逐渐减小;高大山体能有效阻止挡墙水平位移的发展。

In complicated topography, the reinforced earth retaining wall＇s 3-D structural characteristics influence the deformation and stability of the wall. This paper regards reinforced earth as composite material, using modified result of large-scale triaxial tests for reinforced and unreinforced earth, calculates 3-D deformation of retaining wall in an airport with Mohr-Coulomb elastic-plastic model, research shows that： （1）Topography obviously changes the retaining wall＇s deformation, stress lower in high elevation parts, stress decreases gradually when elevation becomes small, in the same elevation, the maximum effective stress happens in the filled soil retaining wall. Retaining wall settlement is more serious in the valley and abruptter place; （2）compared with unreinforeement, maximum horizontal displacement of reinforcement one decreases by 45 %; （3）in the process of retaining wall filling, the horizontal displacement first increases, then decreases; huge mountains prevent the development of the retaining wall＇s horizontal displacement effectively.