Experimental Study On Anisotropy And Non-coaxial Of Wenzhou Soft Clay Under The Variation Of Principal Stress Orientation

The principal stress rotation widely occurs in traffic engineering,Marine engineering,slope engineering,etc.Due to sedimentation conditions,particle orientation and complex loading conditions at the site,the magnitude and direction of the main stress acting on the soil sediments are constantly changing,and the mechanical properties of the soil in different directions,such as stress strain,strength and stress path,all show certain anisotropy.During the process of principal stress axis rotation,the direction of plastic strain increment is not coaxial with the direction of stress.However,if the non-coaxial characteristics of soil is neglected in practical engineering,the deformation of soil may be underestimated,which may lead to the unsafe state of engineering design.By studying the anisotropy and non-coaxial characteristics of soil element when the direction of major principal stress changes,the stress state of soil can be simulated more realistically,so as to guide engineering practice.At present,the influence of principal stress rotation on the non-coaxial characteristics of soil is mostly concentrated in sandy soil,and the corresponding stress path is mainly the minor rotation of principal stress axis.Many relatively dense traffic engineering and ocean engineering are distributed in southeast coastal regions and soft clay layers with complex engineering characteristics are widely distributed in this area.Therefore,it is of great significance to study the anisotropic and non-coaxial characteristics of soft clay under the rotation of the principal stress direction for the accurate prediction of soil deformation characteristics and rational design.Taking Wenzhou soft clay as the research object,a series of laboratory unit tests carried out to explore the anisotropy and non-coaxial characteristics of soft clay under tests of fixed direction shear and major principal stress rotation considered different major principal stress consolidation state.The main research work of this paper is as follows:...