Abstract In this paper, a computational framework based on the Material Point Method is developed to study the coupled seepage-deformation process in unsaturated soils. Governing equations are derived from the balance equations of solid and liquid phases accounting for partial saturation effects, and the soil is discretized with a single set of material points which move according to the displacement of the solid phase. The implementation of different types of boundary conditions, such as transient hydraulic head, seepage face, and infiltration/evaporation, is discussed in detail. The method is applied to simulate levee collapse due to rapid drawdown and rainfall. The methodology proposed in this paper is a promising tool to advance the current practice, which customarily evaluates slope safety only by means of small deformation analyses based on FEM or LEM, while here a large deformation approach is presented.

中文翻译：

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非饱和土的两相动态 MPM 公式

摘要 本文建立了基于材料点法的计算框架来研究非饱和土的渗流-变形耦合过程。控制方程是从考虑部分饱和效应的固液相平衡方程推导出来的，土壤被离散化为一组根据固相位移移动的材料点。详细讨论了不同类型边界条件的实现，例如瞬态水头、渗流面和渗透/蒸发。该方法用于模拟由于快速下降和降雨引起的堤防坍塌。本文提出的方法是推进当前实践的有前途的工具，