列车荷载对路堤式加筋土挡墙结构力学特性影响的数值模拟

利用有限元计算软件PLAXIS, 建立路堤式加筋土挡墙在列车荷载作用下的计算模型, 并且通过与垂直土压力和水平土压力的实测值和理论计算值相对比, 肯定了模型的合理性。进一步改变加筋间距与填土高度, 探讨了加筋土挡墙在列车荷载作用下水平土压力、面板水平位移和筋材最大拉力的变化规律。结果表明:同一高度的垂直土压力值沿筋长方向呈增加趋势;水平土压力值随填土高度增加而增加, 沿墙高方向值变小。增加拉筋间距, 会使水平土压力值、面板水平位移和筋材最大拉力均增大。降低填土高度对墙背水平土压力、面板水平位移和筋材最大拉力的影响较小, 在施加列车荷载后2种曲线均近乎重合。在列车荷载作用下, 可通过增大加筋间距和降低台阶填土高度来优化加筋土挡墙的整体性能。

Numerical Simulation on the Influence of Train Load on the Structural Behaviors of Reinforced Earth Retaining Wall Embankment

A calculation model of reinforced earth retaining wall embankment under train loads was established by using two-dimensional finite element software PLAXIS. The rationality of the model was proved by comparing the measured and calculated values of vertical and lateral earth pressures. Moreover, by changing the reinforcement spacing and soil-filling height, the variation regularity of lateral earth pressure, horizontal displacement of wall panel as well as maximum tension of reinforcement material was analyzed. Results show that: at a given height, the vertical earth pressure increased along the reinforcement length direction; the lateral earth pressure increased with the increase of filling height and decreases along the wall height direction. The lateral earth pressure, the horizontal displacement of panel and the maximum tension of reinforcement material all increased with the increasing of reinforcement spacing and changed a little with the filling height decreasing. The overall performance of reinforced earth retaining wall under train loads can be optimized by increasing reinforcement spacing and reducing filling height.