Large strain nonlinear consolidation analysis of sand drain foundation considering smearing effect
Assuming that the seepage in the soil conformed to non-Darcy seepage,the nonlinear compression characteristics of soft soil were described by introducing a double logarithmic model between effective stress,permeability coefficient,and void ratio.A large deformation consolidation model for sand drain foundation that could simultaneously consider the smearing effect was established,and the model was solved using finite difference method.The reliability of the solution was verified by comparing the degenerate numerical solution with the analytical solution under equal strain conditions and existing experiments.The parameters that affect the nonlinear consolidation of sand drain foundation were analyzed.The results show that among the three modes of considering the smearing effect,the fastest consolidation occurs when the permeability coefficient of the smearing zone changes parabolically,and the slowest consolidation occurs when it is a constant.Compared to a constant permeability coefficient,when the permeability coefficient of the smearing zone changes linearly,the maximum relative deviation of consolidation degree reaches 35.7％,and the maximum relative deviation of settlement amount reaches 26.7％.When the permeability coefficient of the smearing zone changes in a parabolic pattern,the maximum relative deviation of consolidation degree reaches 36.9％,and the maximum relative deviation of settlement amount reaches 28.4％.As the compression index and permeability index in the double logarithmic coordinate system increase,the consolidation rate of the sand drain foundation slows down.When the compression index increases,the final settlement increases,while the permeability index does not affect the final settlement.Compared to the compression index Ic=0.08,the maximum relative deviation of consolidation degree reaches 21.7％when Ic=0.1,and the final settlement deviation is 0.030 m.When Ic=0.12,the maximum relative deviation of the consolidation degree reaches 37.9％,and the maximum deviation of settlement reaches 0.059 m.Compared to the permeability index a=6,the maximum relative deviation of consolidation degree reaches 39.3％when a=10,and even reaches 61.9％when a=14.Considering non-Darcy seepage,the consolidation rate of sand drain foundation is slower,and the maximum relative deviation of consolidation degree can reach 16.5％.
万方数据
维普
