基于软粘土微观特性的非线性固结理论研究

The land subsidence of soft clay is including natural and man-made content, which leads to the research on the mechanism of land subsidence constituted by two different aspects, which are studied by geological engineers and geologist. The main major research is focused on the effects of engineering. The land subsidence engineering of soil mechanics is caused by the consolidation and compression of soft clay, the content of which is including the micro-structural characteristics, the stress - strain constitutive relation, porous law, and consolidation theory. In this paper, it is discussed the nonlinear consolidation and compression theory of soft clay. The main studies and conclusions of this thesis are as follows. （1）The micro-structure and its stability are closely related to the engineering characters of soft clay. The stiffness and force connection status of micro-structure plays a controlling influence to its stability. （2）Under saturated state, clay particles remain in a non-full contact or non-contact status, so it is needed to modify the Terzaghi effective stress principle. With the discharge of pore water, the effective stress is increasing, and part of weakly bound-water begins flow, while the porosity and permeability are became lower. （3）It exist non-linear flow in soft clay, which is caused by the shear flow situation of weakly bounded-water. In this case, permeability coefficient is a nonlinear function of hydraulic gradient. （4）In the initial consolidation stage of soft clay in the initial stage, the porous flow is mainly caused by the excretion of free water. With the decrease of free water content, combined bonded-water start to supply free water. At the later stage of consolidation, the flow of fluid is mainly consisted by weakly bounded-water. The exchange between bonded-water and free water is played a role, which slows down the consolidation process.