Shear Creep Properties And Parameters Of Silty Clay In Huainan Area

In recent years,with the rapid development of Chinese economy,the field and scale of engineering construction are also increasing.Therefore,more and more challenges are faced.One of the difficulties is the study of the time and deformation characteristics of foundation soil under complex conditions.In the process of engineering design and construction,if the time deformation characteristics of rock and soil are neglected,serious engineering problems will be produced,resulting in great security risks.Silty clay is widely distributed in China.Its main physical and mechanical properties are high shrinkage,high expansion,high water content and low shear strength.These physical and mechanical properties lead to significant deformation.In this paper,based on the research status of soil rheological properties,the undisturbed and remolded silty clay as the research object,carried out a series of indoor direct shear creep test on different vertical stress,shear stress and different water content under the condition of direct shear creep characteristics of silty clay.The nonlinear rheology theory is applied to analyze the shear rheological properties of silty clay,and its relationship with time,stress state,structure and moisture content is explored,and the corresponding constitutive relation model and rheology theory are put forward,which has certain theoretical value.The Burgers component model is used to describe the shear creep characteristics of silty clay in Huainan area,and the appropriate data processing method is used to solve the parameters in the Burgers model.The applicability of Burgers model and empirical model is judged by comparing with the experimental data.At the same time,the long-term strength of silty clay and its influencing factors were deduced according to relevant theories.The main conclusions are as follows:(1)By comparing the correlation coefficient,we can see that the function form of power function is in good agreement with the experimental results,so we use a slightly modified power function to fit it.(2)Taking the result of the test of the original soil as an example,the relationship between the shear modulus of the silty clay in Huainan and the time and the vertical stress is obtained.(3)The long term strength increases with the increase of vertical stress,and decreases with the increase of water content.The shear strength index decreases gradually during the creep process,and the relationship is described with exponential function.The cohesion change is larger and the change of internal friction angle is small.It can be concluded that the decrease of long-term strength in Huainan is mainly due to the decrease of cohesive force.