Research Initiation: Response of Saturated Silty Soils to Irregular Seismic Loads

世界上大多数人口稠密的地区都集中在 山谷，也就是说，在沉积矿床组成的不同 无粘性和粘性土壤层，包括非塑性和 塑料淤泥 地震动放大现象 在沉积物中，以及在沉积物中承载能力的丧失， 所有类型的土壤，以及饱和桑迪或粉土的液化 土壤由于地震震动，只是部分了解。 的 如果所有土壤材料（砾石，沙子，淤泥， 粘土）在不规则的地震荷载下必须知道， 了解以上现象。 该研究项目涉及实验室调查， 饱和粉质土响应的分析模型 不规则地震荷载 对应的载荷条件 将在实验室中模拟地震波的传播 使用循环直接简单剪切和循环三轴装置。 循环荷载作用下土壤刚度的退化， 循环孔隙水压力的变化规律， 正在研究循环应力-应变行为。 结果 得到的粉质土进行了比较， 在砂和粘土上的可用结果。 这种比较提供了一个 为发展数学模型的基础上减少 刚度和孔隙水压力的发展，适用于所有 三种土壤。

Most of the populated regions of the world are concentrated in valleys, that is, on sedimentary deposits composed of different layers of cohesionless and cohesive soils, including nonplastic and plastic silts. The phenomenon of the amplification of ground motion in sedimentary deposits, as well as the loss of bearing capacity in all types of soils, and the liquefaction of saturated sandy or silty soils due to earthquake shaking, are only partially understood. The engineering properties if all soil materials (gravel, sand, silt, clay) under irregular seismic loads must be known in order to fully understand the above phenomena. This research project involves a laboratory investigation and analytical modelling of the response of saturated silty soils to irregular seismic loads. Loading conditions corresponding to the propagation of seismic waves will be simulated in the laboratory using cyclic direct simple shear and cyclic triaxial devices. Degradation of soil stiffness during cyclic loading, the associated variation of cyclic pore pressure, and the rules governing irregular cyclic stress-strain behavior are being investigated. The results obtained for silty soils are being compared to the corresponding available results on sands and clays. This comparison provides a basis for the development of mathematical models for the reduction in stiffness and the development of pore water pressure, valid for all three types of soils.