Experimental Research on Difference of Dynamic Modulus and Damping Characteristics of Loess in Shanxi Province

Abstract

Dynamic triaxial tests are carried out on loess from different regions in Shanxi province. Based on the test results, dynamic constitutive relation, dynamic modulus and damping ratio behaviors of the loess are studied. Influence of regional distribution, physical indexes and ages on dynamic modulus and damping ratio of the loess are analyzed by comparing the model parameters. The results show that dynamic constitutive relation of Shanxi loess conforms to hyperbolic model. The relationship between the dynamic shear modulus ratio and the dynamic shear strain can be described as a negative exponential function. However, the relationship between the damping ratio and the dynamic strain obeys to a power function. The maximum dynamic shear modulus tends to increase from south to north. Moreover, there is a good correlation between dynamic shear modulus ratio and initial void ratio. The variation trend of dynamic modulus changing with dynamic shear strain is related to natural moisture content of the loess, and the value of dynamic shear strain in the central part of Shanxi province is bigger than that in south and north. While that in the north is the least. The increasing tendency of damping ratio has obvious regional differences which have been greatly affected by the natural moisture content and ages.