Experimental Study And Numerical Simulation On Shear Strength Of Starch Clay

With the gradual deepening of the construction of Xiongan New Area and the increasing construction of the project,the further study of the mechanical properties of the foundation soil in Baiyangdian area,where Xiongan New Area is located,has important engineering value.Aiming at the silty clay in Baiyangdian area of Anxin County,this paper carries out a series of experimental studies and numerical simulation,and synthetically compares and analyses the experimental and numerical results in order to provide some reference for practical engineering construction.The main contents of this paper are as follows:(1)Determine the physical properties of the sampled soil,and then carry out indoor compaction test to determine the distribution of dry density value of the sampled soil under the same compaction work and different water content conditions.The maximum dry density and optimal water content of the sampled soil can be obtained,which provides the basis for subsequent unconfined compressive strength test and triaxial test.The variation of dry density of silty clay specimens with the same moisture content and different compaction work was compared.(2)Through triaxial tests,the variation of stress-strain curve and shear strength of soils under different confining pressures and shear rates is obtained.The relationship between failure strength and confining pressure as well as shear rate is fitted by analyzing and sorting out the data obtained from the test,and the specific functional relationship is obtained.Finally,the relationship between internal friction angle,cohesion and shear rate is analyzed and studied through Mohr-Coulomb failure criterion.(3)The stress-strain curves of specimens under different dry densities and moisture contents are obtained through the unconfined compressive strength test of specimens.Then the relationship between dry densities,moisture contents and unconfined compressive strength is fitted and analyzed,and the specific functional relationship is obtained.Finally,the influence of dry density and water content on unconfined compressive strength of soil is discussed.(4)Using ANSYS software to simulate the triaxial shear test of soil samples,the physical and mechanical parameters of soil samples obtained from the test are compared with the results of standard triaxial test in laboratory,and the numerical simulation is verified.