Study on liquefaction mechanism and pore-water pressure mode of saturated original loess

The increasing rhythm of pore water pressure was discussed by tests on saturated original loess, and the liquefaction mechanism of saturated original loess was analyzed in terms of microstructure. The results of tests indicate that the structure of saturated loess which does not slump is metastable and the force of earthquake can cause loess structure to failure. Larger volume strain may be caused by collapse and shear shrinkage. The increasing curves of pore water pressure can be fitted in modified A-curves presented by the authors. The parameter β implies the influence of magnitude of dynamic stress on the development of pore water pressure, while the volume strain ν reflects the influence of moisture slump on the development of pore water pressure, and the model of curves is controlled by the combination of different β and ν values. The reason why loess in Tajik and Haiyuan earthquakes can flow like a fluid in the gentle slope would be explained by the liquefaction mechanism.