Experimental Study on Liquefaction Characteristics of Saturated Sand–Silt Mixtures

Soft soil layers, such as sand and silt, are prone to seismic liquefaction when exposed to ground shaking induced by earthquakes. Many severe earthquake disasters in history can be attributed to weak ground conditions. While the dynamic behavior of sandy soils and silts has been widely investigated, real‐world liquefiable sites often consist of soils with varying fines contents (FCs) rather than uniform compositions. A DYNTTS‐type cyclic triaxial testing device was used to investigate the liquefaction behavior of saturated sand–silt mixtures under isotropic consolidation ( K c = 1.0), with an effective confining stress of 100 kPa and a vibration frequency of 1 Hz. The influence of cyclic stress ratio (CSR), FC, and relative density ( D r ) on dynamic pore pressure in saturated sand–silt mixtures was investigated through a series of cyclic triaxial tests. The development of dynamic pore pressure is closely related to the CSR. FC and relative density ( D r ) have a significant influence on the empirical constant ( θ ). The effect of FC on the dynamic strength of saturated sand–silt mixtures was subsequently investigated, along with an analysis of the underlying mechanisms.