Abstract: The GDS dynamic triaxial testing system was used to study the reloading feature of liquefied tailings silt. First， the saturated tailings silt was liquefied by cyclic loadings， then， the static loadings were applied to the liquefied tailings silt. The deformation and pore water pressure of the liquefied tailings silt were experimentally studied， with confining pressure， relative density and loading rate considered. The results show that， the confining pressure and relative density impact on the deformation of liquefied tailings silt obviously， while the loading rate has little effect， under undrainage condition. Pore water pressure ratio is usually between 0.7~0.9 at the end of the experiment. Relative density has greater impact on the pore water pressure than confining pressure. Based on the experimental data， a new three-parameter constitutive model of liquefied tailings silt is presented and the model parameters are determined by fitting. It is validated that the model proposed has good applicability and forecast precision.

Key words: tailings silt, pore water pressure, liquefaction, deformation, constitutive model