Study On Deformation And Pore Pressure Of Saturated Soft Clay Under Three-dimensional Stress Path

There exists plenty of saturated soft clay in southeast coastal area of China,most of which is flood-plain deposit soft soil or deltaic strand facies.The problematic issues such as deformation and strength of the saturated soft clay under various complex static and dynamic stress paths are a hard nut to crack,which has stood in the way of the economic development of the southeast coastal area of China.Simulating the real situation of the saturated soft soil under the complex stress path shall provide all of us with the access to the response or the evolution law of how the saturated soft clay performs and it also lead us find a way to possess the method to compute its constitutive relation and be more ready to grasp its bearing capacity.It is found t hat the actual traffic load is a kind of cyclic load.In this engineering condition,the stress path of soil element is rather intricate.It works as the multi-dimensional coupling of load in parallel direction and the vertical direction of the foundation soil in three dimensions space,which have a great and common influence on the mechanical response.Accordingly,we simulate the real process of how the saturated soft clay in the southeast of China consolidated and loaded,and then do a series of experime nts under the complex coupling static and dynamic stress path,via the application of Wenzhou University GDS true triaxial test apparatus.The details are listed as follows:A series of dynamic cyclic test on soft clay under horizontal-verbal coupling stress path has been done.The evolution law of cyclic elastic and plastic strain,cyclic pore pressure,rebound modulus and hysteretic curve under vertical-horizontal coupling cyclic stress path are studied by doing cyclic undrained experiment on the saturated soft clay samples.A group of true triaxial tests under the coupling influence of cyclic shear stress level and cyclic stress ratio are performed,and with that,the response of cyclic strain,cyclic pore pressure,the hysteretic stress-strain curves from which the strain energy is calculated to describe the deformation of soil is discussed as well.Simultaneously,a rectification model that is used for indicating the settlement of saturated soft clay distributed in China's southeast regions under the vertical-horizontal coupling cyclic stress path based on exponential model is proposed.