Experimental Study On Dynamic Behavior Of Saturated Soft Clay Under Two-way Shear Stress Coupling Under Complex Shear Stress Paths

The actual engineering load for dynamic load periodic(cyclic load),seismic load is a kind of common cyclic load,and the stress condition of the soil under the stress path is very complex,one of the important reasons is the complexity of multi coupling cyclic stress,not only the horizontal load amplitude of cyclic change load,frequency and direction will change.To carry out multi coupling cyclic shear test aims at reducing seismic load of soil under the real stress state,is of great significance to study the dynamic deformation characteristics of saturated soft clay under seismic load.China is located in the two earthquake zone at the junction,the earthquake disaster is serious,in the complex dynamic stress coupling field of soft clay because of its low strength,strong compressibility,high sensitivity,high water content and poor engineering properties such as easy deformation or damage and lead to the upper part of the building and Engineering disaster caused failure,therefore,for soft clay two-way coupling stress are studied under the action of damage mechanism is conducive to soft clay under seismic load and the corresponding development of the disaster technology research,and then carry out the appropriate reconstruction measures.In this paper,a series of biaxial shear tests under complex stress paths are carried out for a typical remolded soft clay sample in Wenzhou using a complex multidirectional cyclic shear apparatus,which mainly includes the following work:Through the cyclic simple shear apparatus,according to the "8" form of stress path under the horizontal coupling cyclic shear test,discussed under undrained conditions of remolded soft clay of Wenzhou should be saturated samples under different cyclic strain stress level,stress strain hysteresis loop response,dynamic shear modulus and strength characteristics and explores.The relationship between bidirectional loading frequency and shear strength,the frequency of failure number formula,provide the basis for the study of cyclic shear behavior following two-way coupling.The cyclic simple shear apparatus of initial shear stress under cyclic strain should be elliptical soft clay in Wenzhou under the stress conditions,stress strain hysteresis curve and the dynamic evolution law of strength,and compared the different effects of initial shear stress on the dynamic response characteristics of undisturbed saturated soft clay.The cyclic simple shear apparatus carried out a series of two-way coupled cyclic stress path tests of saturated soft clay should be dynamic strain,stress path under the dynamic strength in different development,should change stress strain hysteresis curve,deformation of soft soil and under different loading paths of evolution are compared analysis.