Study On Static And Dynamic Mechanical Characteristics Of Sandstone And Sand Compound Soil

At present,many studies have pointed out the feasibility of using sandstone as a building material and dam material.However,the research on the sandstone is mosllv focused on the exploration of its physical properties and static mechanical prop erties.There are few studies on the dynamic mechanical properties of the sandstone and sand compound soil.Studying the static and dynamic mechanical properties of sandstone and sand compounding soil is of great significance for solving practical engineering needs.Taking the typical reddish-brown sandstone in the Mu Us area as the research object,the static and dynamic constitutive relations of the sandstone and the sand compounding soil,and the variation law of the dynamic modulus and dnamping ratio of the compound soil are studied.Through control of different imitial conditions,indoor peretration test,compression test,direct shear test,triaxial shear test,etc.,analysis of initial conditions such as mass ratio,water content and dr y density for static mechanies of sandstone an d sand compounding soil According to the influence of the index,the infiltration law,compression characteristics and shear characteristics of the sandstone and sand compound soil were studied,and the staticconstitutive characteristics of the sandstone and sand compound soil were revealed.The triaxial specimens of the sandstone and Fujian standard sand compound soil were prepared according to a certain mass ratio,dry density and water content.The indoor consolidation and undrained dynamic triaxial test was carried out by GDS soil triaxial apparatus.The dynamic character istics of composite soil samples under the action of half-sinusoidal dynamic load are explored.The stress-strain characteristics of the sandstone and sand compound soil samples in the case of large dynamic strain are analyzed,and the sandstone and sand complexes are found.The dynamic stress-strain curve of soil conforms to the hardening failure trend,and the dynamic stress-strain constitutive parameters of compound soil under different initial conditions are fitted.According to the results of dynamic triaxial test,the effects of mass ratio of strontium sandstone and sand on the stress-strain characteristics of composite soil under cyclic dynamic loading and the influence of different initial conditions on the dynamic strength of composite soils with large failure strain are analyzed.The optimum mass ratio of the sandstone to the sand compounded soil is pointed out.The relationship between the dynamic shear modulus and the damping ratio of the compound soil is determined,and the dynamic shear modulus of the compound soil is established.-Dynamic shear strain model,and damping ratio-logarithmic empirical formula of dynamic shear strain.