Liquefaction of deep overburden layers in zones with high earthquake intensity

The vibrating liquefaction of sandy soils is subjected to various factors, among which, the embedment depth (stress state) is a very important factor. The centrifugal shaking table tests are carried out to investigate the dynamic response and liquefaction rules of deep sand layers. For the problem that the deep soil layers cannot be simulated by the centrifugal shaking table, a loading air bag to simulate loads of overburden layers is designed. By controlling the pressure in the air bag, the seismic response situations of sandy layers with different embedment depths can be simulated. Accordingly, the stress similarity conditions of deep foundations are satisfied. Four kinds of test conditions are arranged, which respectively correspond two kinds of embedment depths and two kinds of vibrating frequencies. The response rules of acceleration and excess pore water pressure in the sand foundation with various embedment depths are released, and the influences of the vibrating frequency on the vibrating characteristics of deep sand foundations are discussed. It may provide a satisfactory way for judging the seismic liquefaction of deep sand foundations.