Soil deformations close to retaining walls due to vibration excitations

目前的子项目处理的积累现象，饱和土壤在高周波荷载引起的岩土工程施工过程中，如振动打桩附近的挡土墙。根据现场条件（土壤类型、密度、饱和度、排水、渗透性），各种安装过程或方法可能导致有效压力降低、土壤液化、蠕变行为，并因此导致大变形。还应考虑施工构件的安装顺序及其对相邻结构变形的影响。该研究将包括在数值解的动态边界值问题的循环加载的目的是找到振幅场，永久性变化的有效应力和由此产生的变形。最后，它的目的是提出一种预测变形的方法，作为实际建议的基础。

The present subproject deals with accumulation phenomena in saturated soils during high-cycle load-ing caused by geotechnical construction processes such as the vibratory pile driving in the vicinity of a retaining wall. Depending on the in-situ conditions (soil type, density, degree of saturation, drainage, permeability), various installation processes or methods can lead to the reduction of the effective pressure, soil liquefaction, creep-like behaviour and, as a consequence, to large deformations. The sequence of the installation of construction elements and their effect on the deformation of the neighbouring structures should also be taken into account. The study will consist in the numerical solution of dynamic boundary value problems for cyclic loading with the aim of finding the amplitude fields, the permanent changes in the effective stresses and the resulting deformations. Eventually, it is intended to suggest a method of prediction of deformations as a basis for practical recommendations.