TEST STUDY ON MICRO-MECHANISM OF IMPACT LIQUEFACTION OF SANDY SILT

Engineering geology issues raised by earthquake-induced soil liquefaction have been drawn particular public attention. Studies focused on the formation mechanism of impact load-induced liquefaction and associated influencing factors are remarkably limited. This study conducts a series of impact load liquefaction tests on the sandy silt and its micro structure analyses towards revealing the development of pore pressure and the change in micro structure. The results indicate that impact load aggravates the development of pore pressure and its magnitude decreases with increase of impact energy. The micro structure analyses showed that impact load also causes a change in interparticle contact,particle morphology,and pore structure. Soil skeleton damages and pore shrinkage are deemed as the main cause to lead to soil liquefaction when subjected to impact load. The formation mechanism varies depending on the level of soil skeleton damage and pore shrinkage.