Experimental study and correction of dynamic characteristic parameters of silty clay under negative temperature conditions

Abstract

In order to examine the principles governing the variation of dynamic characteristic parameters, including the damping ratio, dynamic modulus, and frozen soil backbone curve, under different negative temperature conditions, silty clays sourced from the Changchun region were selected for the research. Dynamic loading studies were carried out on silty clays under different negative temperature conditions using a temperature-controlled GDS dynamic triaxial machine. The results demonstrated that the lower the temperature, the higher the dynamic stress required to achieve the same dynamic strain. The inverse of the dynamic modulus $1/E_d$ is linearly related to the dynamic strain, and the intercept of the fitted line of the inverse of $1/E_d$ decreases with decreasing temperature. The damping ratio and ability to absorb vibration waves decrease as the temperature drops. As the temperature decreases, the maximum dynamic modulus gradually increases, and the maximum damping ratio has the opposite trend. The temperature correction formulas for the maximum dynamic modulus and maximum damping ratio of silty clay are proposed by correlation analysis method based on test data.