DEM analysis of undrained cyclic simple shear test on saturated sand

抄録

Liquefaction can be considered to occur in saturated sand widely under seismic load, which will cause serious disaster, including road damage, ground subsidence, cracking of houses. Thus, it is quite necessary to study the liquefaction characteristics of saturated sand. For this aim, the undrained simple shear test on saturated sand under cyclic loading were simulated by three-dimensional distinct element method (DEM), where the stress-strain relationship, excess pore pressure ratio, mechanical coordination number and contact normal direction were analyzed. The results show that the liquefaction of saturated sand is manifested by the accumulation of excess pore pressure ratio. In addition, the mechanical coordination number gradually reduces and the sample anisotropy slightly fluctuates before the saturated sand reaches initial liquefaction. When the specimen approaches initial liquefaction, the mechanical coordination number drops abruptly and the sample anisotropy obviously increases.