Abstract:Saturated fine sand is widespread under the Jiangling section of the Jingjiang levees, so a system test of the levees' dynamical properties is necessary. Using specimens built with reference to in situ test results with an estimated consolidation stress ratio Kc (approximately 1.6), we conducted a series of dynamical triaxial tests to study the dynamical elastic modulus, damping ratio, and dynamical strength. The results are as follows:(1) The relationship curves of the dynamic stress-strain of the specimens and the Hardin-Drnevich hyperbolic model assumption match well, and Hardin's formula is also a good fit with the relationship between the dynamic modulus/damping ratio and dynamic strain. In the actual compactness range of the specimens, the maximum dynamic modulus increases with increase in the confining pressure and compactness, and the confining condition is more sensitive. Furthermore, with the same confining pressure but different compactness, the fitting curves of the shear modulus ratio and the dynamic strain nearly coincide. In addition, the damping ratio decreases with increase in the confining pressure and compactness, and when the dynamic strain is 1%, the corresponding damping ratio for specimens with different conditions ranges from 0.15 to 0.21. (2) Under bias-consolidation conditions, we set a cumulative axial strain of 5% as the liquefaction standard. With increases in the confining pressure and number of dynamic cycles, the dynamic shear stress ratio decreases, and the maximum dynamic pore pressure ratio can only reach 0.8~0.9. (3) The dynamic friction and cohesion obtained by the total stress method decrease with increases in the number of dynamic cycles. In addition, the cohesion of the specimens is not approximately equal to 0, which indicates a viscosity characteristic of saturated find sand under dynamic action.