地震荷载作用下加筋土挡墙动力特性分析

Dynamic Characteristic Analysis of Reinforced Earth Retaining Walls under Seismic Load

摘要:

利用有限元软件对加筋土挡墙在地震荷载作用下的动力特性进行模拟分析，重点分析其在不同加筋长度、加筋间距以及峰值加速度条件下的动力响应特性。通过有限元分析一个高6 m、底部为基础土的加筋土挡墙在地震荷载作用下的行为，针对理想化墙体研究加筋土挡墙的某些动力特性。模拟计算结果表明加筋土挡墙的加筋长度、加筋间距以及峰值加速度的变化对其水平位移、沉降及受力有较大影响。采用长度大的加筋材料可以有效减小加筋土挡墙的水平位移，但这样将导致加筋拉伸荷载的增大，同时也将导致加筋土挡墙的隆起增大。峰值加速度的大小对加筋土挡墙的水平位移有很大影响，当峰值加速度增大时水平位移也随之增大，但并不呈线性增长关系。减小加筋间距会有效地限制加筋土挡墙面板整体的水平位移，但在一定范围内减小加筋间距也会使加筋区域内土体底部挡墙的水平位移出现相对增大的现象，因此通过减小加筋间距来限制加筋土挡墙的位移在一定程度上具有局限性。

Abstract:

In this study, the dynamic properties of reinforced earth retaining walls under seismic load were analyzed by using Plaxis, a finite element analysis software program. The analysis focused on the dynamic response characteristics of the wall under the influence of different reinforcement lengths, reinforcement spacing, and peak acceleration, assuming an ideal wall with a height of 6 m and a base in foundation soil. Through simulations, it was determined that changes in reinforcement length, reinforcement spacing, and peak acceleration had the strongest influence on the horizontal displacement, vertical settlement, and stress in the reinforcement materials of the earth retaining wall. The horizontal displacement of a wall can be effectively reduced by using reinforced materials of longer length. However, this will lead to an increase in reinforced tensile load, and an uplift of reinforced earth retaining wall. The value of peak acceleration has the greatest influence on the horizontal displacement of wall. Although increases in horizontal displacement result from increases in peak acceleration, it is not a linear relationship. Decreases in reinforcement spacing can also effectively limit the overall horizontal displacement of wall, however, across a certain range, it can result in a relative increase in bottom of wall horizontal displacement. Therefore, reducing the displacement of a wall by decreasing the reinforcement spacing is only useful to a limited extent.