考虑变形非线性影响的有限土体土压力计算模型

分析了墙后有限土体的破坏模式及位移特征。对墙后土体梯形滑动楔体进行分区处理，分别采用薄层单元法建立了极限状态土压力强度一阶微分方程，导出了有限土体极限土压力理论公式。在此基础上，考虑土压力的非极限状态与极限状态的关联性，建立了土体位移与土压力的关系式，提出了考虑土体位移非线性影响的有限土体土压力计算模型。该模型可考虑围护结构扰曲变形等非线性位移对土压力发挥的影响，且参数简单物理意义明确。与试验实测数据对比表明，该方法相比规范方法更接近于实测值，可供相关设计计算参考。

Calculation model of the earth pressure for limited soils considering the nonlinear influence of the displacement

Firstly, the failure mode and the deformation characteristics are discussed in the paper. Then, the trapezoid-slide soil is divided into two parts and the differential equation of first order about the earth pressure intensity is set up by using thin-layer element method, so the theoretical formula of active earth pressure for limited soil is deduced. Based on this, the calculation model of the earth pressure for limited soils which can consider the nonlinear influence of the displacement is established by taking the relationship between the displacement of soil and the earth pressure into account, moreover, the parameters of the calculation model is easy to determined and has specific physical meaning. Finally, the comparison shows that earth pressure calculated by the method presented in the paper is much closer to the measurement data in the model test than the standard method.