粗颗粒土的静止土压力系数非线性分析与计算方法

确定静止土压力系数在土压力计算中非常重要，但是粗颗粒土的静止土压力系数非线性特征长期被忽视，专门研究其非线性特征具有重要现实意义。为弥补粗粒土K0非线性研究的不足，分析了粗颗粒土的静止土压力系数非线性特征。基于邓肯?张模型的应力?应变增量关系，引入邓肯?张模型参数，建立了静止土压力系数数学公式。同时，提出了粗颗粒土静止土压力系数非线性计算方法，并对公式参数敏感性进行了分析。基于K0试验数据和数值试验结果，对粗颗粒土静止土压力系数非线性计算方法进行了应用分析。应用结果表明：K0预测值与K0实测值吻合，所提出的非线性K0计算方法可用于粗颗粒土K0计算。通过与Jaky公式的结果的对比分析，讨论了初始应力条件对粗颗粒土静止土压力系数非线性计算结果的影响。该研究成果有助于加深对土体静止土压力系数非线性的理解，并为粗颗粒土静止土压力系数计算提供参考。

Analysis of the nonlinearity of coefficient of earth pressure at rest and its calculation method for coarse-grained soils

The acquisition of a precise coefficient of earth pressure at rest (K0) is very important for earth pressure calculation, and the study of nonlinear characteristics of K0 has great practical significance. Nevertheless, the research on nonlinearity of K0 for coarse-grained soils has long been neglected. To fill the gap, this study presents a detailed analysis of the nonlinearity characteristics of K0 for coarse-grained soils. Based on the incremental stress-strain relation of Duncan-Chang model, we establish the mathematical formula of K0, and the sensitivity analysis of the K0 formula is presented. The proposed method is applied to predict the K0 of coarse-grained soil experimental data reported by others and by DEM method. Comparison results show that the calculated K0-value is very close to the experimental K0-value, particularly for coarse-grained soils. Furthermore, we compared the K0-value from Jaky formula and that from the proposed method, and discussed the influence of initial stress condition on K0 for coarse-grained soils. The research findings of this study are helpful for the understanding of nonlinearity and the precision of K0 in coarse-grained soils, and may provide reference for related earth pressure calculations.