Dynamic Loading of Partially-Saturated Soil: an investigation in the framework of numerical mechanics of strongly coupled problems

无论是复杂的基础，还是在现有环境下建造所需的基础技术（如打桩或振动），都必须基于对新建筑和“整体系统底土”相互作用的详细调查。考虑到这些特点，静态和动态加载条件都必须考虑在内。这些荷载作用于底土，可引起大的变形。承受这些载荷是由由固体骨架、土壤、孔隙流体、孔隙水和孔隙气体组成的底土的各种组成部分相互作用而发生的。当地基受到外力载荷时，初始化了一个时间敏感的弹塑性或弹粘塑性变形过程，从而导致整个地基的准静态或动态耦合变形-流动问题。在这个子项目中，干燥、部分饱和和完全饱和的土壤被考虑，并在由成分的质量和动量平衡产生的强耦合偏微分方程系统的基础上进行数值处理。整体模型基于多孔介质理论，并考虑了地基的小而有限的弹塑性变形。数值研究采用适合于动态问题的隐式和显式时间积分方法相结合的有限元方法进行。

Both complicated foundations as well as foundation techniques necessary when building in an existing context (such as pile driving or vibrating) have to be based on a detailed survey of the mutual interactions of the emerging construction and the “overall system subsoil”. Considering these features, static as well as dynamic loadings conditions have to be taken into account. These loadings act on the subsoil and can cause large deformations. Withstanding these loads takes place by the mutual interaction of the various components of the subsoil consisting of a solid skeleton, the soil, and the pore fluids, pore water and pore gas. When the subsoil is loaded by external forces, a time-sensitive, elasto-plastic or elasto-viscoplastic deformation process is initialised resulting in a coupled quasi-static or dynamic deformation-flow problem of the overall subsoil. Within this sub-project, dry, partially saturated and fully saturated soils are considered and numerically treated on the basis of a strongly coupled system of partial-differential equations resulting from the mass and momentum balances of the components. The overall model is based on the Theory of Porous Media and includes small and finite, elasto-plastic deformations of the subsoil. The numerical investigations are carried out by the Finite-Element Method in combination with implicit and explicit time-integration procedures suitable for dynamic problems.