Experimental Study On Dynamic Shear Modulus And Damping Ratio Of Structural Soil

The dynamic characteristics of soil is one of the main factors affecting the characteristics of ground motion.The dynamic modulus and damping ratio of rock and soil are the primary parameters of geotechnical dynamics,and are the necessary dynamic parameters for seismic response analysis and seismic stability evaluation of geotechnical structures,At present,the research on dynamic shear modulus and damping ratio of soil mainly focuses on the understanding of the differences in dynamic characteristics of soils in different regions,effect of Different Soil on the dynamic characteristics of the physical properties of the soil,static conditions,loading and test methods,there are few related studies on the effects of structural on dynamic shear modulus and damping ratio,which is precisely what is important for soils,therefore,carrying out relevant experimental research is an effective way to correctly understand the influence of soil structure on its dynamic characteristics.Starting from the structural structure of the soil,a series of resonant column tests were carried out by preparing artificial structural sand and soft soil.The dynamic shear modulus and damping ratio were determined through experiments,and the structural parameters of the two parameters were studied.The influence of the influence is analyzed.Finally,the factors of initial dynamic ratio,consolidation confining pressure,relative compactness and cementation degree are compared to the maximum dynamic shear modulus,dynamic shear modulus and dynamic shear modulus ratio.Based on the influence law of the damping ratio,the recommended values of the dynamic shear modulus ratio and the damping ratio of the soil are given.The main work of this paper is as follows:1.Study on the preparation method of structural soilIn this study,cement and sugar were added to pure sand and clay to obtain artificially prepared structural soil samples,simulating the structural and macroporous properties of the soil,and using dynamic resonance column to complete the dynamic shear modulus and damping ratio test.In order to make the test results comparable,this paper also compares structural soil with remolded soil.The soil samples used in this test were all reshaped.2.Experimental study on dynamic shear modulus and damping ratio of artificially prepared structural sandThe dynamic shear modulus and damping ratio of structural sands were studied by using the resonant column experiment of step-by-step cyclic loading.The conditions of cement dosage,consolidation confining pressure and relative compactness were changed in the experiment to draw different influencing factors Gd/Gdmax-? and ?-? curves were used to investigate the relationship between the dynamic shear modulus ratio of structural sand and the nonlinear relationship between shear strain,damping ratio and shear strain.3.Experimental study on dynamic shear modulus and damping ratio of artificially prepared structural soft soilThe dynamic shear modulus and damping ratio of structural soft soil were studied by using the resonant column experiment of step-by-step cyclic loading.The conditions of consolidation confining pressure and pore ratio were changed in the experiment to draw different influencing factors Gd/Gdmax-? and ?-? curves were used to investigate the relationship between the dynamic shear modulus ratio of structural soft soil and the nonlinear relationship between shear strain,damping ratio and shear strain.4.Study on the influencing factors of maximum dynamic shear modulus,dynamic shear modulus and damping ratio of structural soilThere are many factors affecting the dynamic shear modulus and damping ratio of soil.The researches are widely used,such as confining pressure,void ratio and number of load cycles.In this paper,the influencing factors under different test conditions under different confining pressures,different relative densities,different void ratios and different cement contents are constructed.The dynamic characteristics of structural soils are studied,and the dynamic shear of structural soils under different conditions is discussed,the influence of modulus and damping ratio.5.Recommended values for considering the dynamic shear modulus and damping ratio of soilsBased on the relationship between the maximum dynamic shear modulus of structural soil,the dynamic shear modulus ratio and the shear strain nonlinearity,and with reference to relevant research results at home and abroad,a basis for reflecting the soil structure can be given,recommended values for the maximum dynamic shear modulus,dynamic shear modulus ratio,and damping ratio change amplitude.Provide reference for indoor soil dynamic characteristics test,solve the imperative task in engineering,for practical engineering reference and reference.