Study on the pore water pressure of saturated sand in dynamic triaxial test

In the paper, the development of pore water pressure is studied based on the dynamic triaxial test. According to the different behavior of pore water pressure, the process is divided into four phases. Connecting the development of pore water pressure with that of strain and stress path, the authors summarize all kinds of factors which infect the development of pore water pressure, so the mechanism of the saturated sand liquefaction is more clear than before. The phenomenon in the process of sand liquefaction can be explained by the theory of shear contraction, shear dilatation and unloading shrink,the analytic results show that the state of sand stress relates closely to the development of pore water pressure,of which the shear dilatation and unloading shrink are the primary influencing factors also.