Experimental Study On Relation Between Dynamic Elastic Modulus And Shear Modulus Of Soil

For those who are dynamic loads and loads such as seismic waves cyclic loading of the buildings, soil conditions on the ground dynamic load resistance are very significant damage. The driving force for deformation of the soil is the foundation soil conditions constitute an important factor. Dynamic modulus (E, G) is a characterization of the soil dynamic deformation of the important parameters for the dynamic modulus of the initial study, including moving the module to identify and dynamic relationship between the amount of non-linear attenuation.Maximum dynamic shear modulus is an essential design parameters. 3-axis dynamic instrument as opposed to fixed-twisting and cutting instrument coupled test cycle, is easy to use and has simple sample preparation. It uses vertical dynamic elastic modulus conversion dynamic shear modulus to simulate the real situation, dynamic Poisson's ratio in the undrained test check of 0.5. A variety of different kind of soil test results showed that there is a certain degree of difference between actual value and conversion value. The dynamic Possion ratio is effected by an average principal stress, soil bulk density, porosity, stress path, testing methods, initial Consolidation conditions and other factors.This article used data from the test-the-art " Soil Static and Dynamic Universal Triaxial and Torsional Shear Apparatus" The apparatus can simulate the soil conditions of the initial stress, such as in the initial principal stress factor, different stress than the initial partial principal stress and the initial angle, and so on, and the accuracy of measurement can reach the magnitude 10^-5. It can improve the dynamic shear modulus testing accuracy, which is essential. Through data processing in-depth and systematic study about the dynamic change law of Poisson's ratio was made on Fujian Standard sand and the Changjiang River original soft clay. The results showed that:The average principal stress consolidation, the initial major principal stress angle, the partial stress on the soil than the backbone of the curve, the normalized curve in varying degrees. The modulus decay curve, G/G_max～γaverage principal stress and the partial consolidation stress ratio increased so that the same strain amplitude conditions increase the amplitude of the stress so that the soil of the initial dynamic shear modulus increase, and the initial angle of the major principal stress effect is the opposite . In the principal stress factor on the backbone of the soil modulus curve and dynamic non-linear attenuation does not affect the basic relationship. Reference toγ_γthe normalized curves GIG_max～γ/γ_γdoes not introduction of shear strain rely on the above-mentioned factors.The average principal stress consolidation, partial stress ratio, the initial major principal stress angle, the stress of moving the path of Poisson's ratio are affected, in the semi-logarithmic coordinates, the saturated sand and Poisson's ratio moving average principal stress consolidation into line Sexual relations, increasing monotonous. The original soft clay for the monotone decreasing. Linear coordinates, Poisson's ratio as the action-stress ratio increases. With the initial major principal stress increases the angle decreases, while the principal stress factor for the move does not affect the basic Poisson's ratio. This article was calculated through a variety of test conditions, Poisson's ratio of fixed values. The stress of change so that theμ_d～p'_m0 slope of the straight-line relationship changed.