Study On Shear Strength Characteristics And Constitutive Model Of Soft Soil In Dongting Lake Area

With the construction of the highway and railway in Dongting Lake the existing research of soft soil can no longer meet the requirements of engineering construction.Soft soil foundation and soft soil in NanYi highway,as the subject of this article,we did a serious of research to sheer strength features and constructive model of the soft soil in Dongting Lake.Our work are as following:(1)Research on the engineering feature of soft soil in Dongting Lake.Based on the existing engineering feature research of soft soil in Dongting Lake,we conduct a series of basic physical and mechanical tests to get the physical and mechanics parameter of soft soil in Dongting Lake,then by studying and analyzing the correlation between physical and mechanical parameters,we get the regression equation between physical and mechanical parameter of the soft soil in Dongting Lake.(2)Research the rule of sheer strength of the soft soil in Dongting Lake.Due to the stability issue of soft road foundation in Dongting Lake highway,we did large quality of consolidation and direct sheer strength tests studied the charge rule of the sheer strength index cohesion and friction angle of soft soil in Dongting Lake in different consolidation pressure and different degree of consolidation.We get the formula among consolidation degree,consolidation pressure and shear strength index.This giving the reference to the design and construction of the soft road construction in Dongting Lake.(3)Experimental study on relationship of soft soil stress-strain in Dongting Lake.Regarding soft soil in Dongting Lake as the subject of this experiment,we studied the strength and deformation characteristics of soft soil in Dongting Lake.(4)Study on soft soil constitutive model in Dongting Lake.DissThe modified Cambridge model theory was discussed,and then on the basis of laboratory soil test applicable to dongting lake modified Cambridge model of soft soil parameters is calculated;Based on the finite element program ABAQUS,the undrained triaxial drainage shear test and triaxial shear test were simulated,to analysis and comparison the applicability of the modified cam-clay model of Dongting Lake in soft soil and analysis of the effect of modified cam-clay model parameter selection by comparing the numerical simulation results and actual test data.