Research on the evolution and modified model of dynamic characteristics of saturated tailings under different cyclic loading conditions

Tailings pond is a place for storing tailings after beneficiation. The tailings sand is mainly composed of fine sand, fine sand and other non-cohesive soils, which are often in a saturated state. Therefore, under dynamic action, liquefaction is prone to occur and cause instability and damage to the tailings dam. This article takes the Gaowanqiu tailings pond in Shizhuyuan as the research background. Through on-site sampling, the basic physical properties and physical parameters of tail silt, Tail floury sand, and tail silty clay were tested. The dynamic parameters of tailings samples, including stress–strain relationship, axial strain characteristics, pore pressure characteristics, and dynamic strength characteristics, were tested using the DYNTTS dynamic triaxial testing system to investigate their dynamic characteristics under different confining pressures and dynamic stress ratios. Based on dynamic triaxial tests of different types of tailings samples, modified models for dynamic pore pressure and dynamic strength, as well as dynamic pore pressure and dynamic strain, were constructed. A modified model for dynamic pore water pressure of tailings materials during vibration was constructed by modifying the Seed model, and a dynamic pore pressure dynamic strain relationship model suitable for tailings materials was constructed by linearly expressing the relationship curve between pore pressure and strain of tailings materials. The model is in good agreement with the experimental results and can accurately predict the relationship between dynamic pore pressure and dynamic strain of tailings materials.