Study On One-dimensional Consolidation Theory Of Structured Soft Soil By Considering Non-darcy Flow

Structural property of natural soft clay and the phenomenon that the seepage in soft clay may deviate from Darcy's flow law under low hydraulic grade have been gradually recognized by researchers,but the consolidation theory of structural soil with Hansbo non-Darcian flow has not been reported.Based on Terzaghi's theory of consolidation and classical Hansbo's non-Darcian flow model,a nonlinear consolidation model is developed by considering the structure of natural soil and time-dependent load in practical engineering,the finite difference method is adopted to obtain numerical solutions for this model.Based on the reliability of numerical solutions,the influences of non-Darcian flow and soil structure on consolidation behavior of structural soft soil with non-Darcian flow are analyzed.The main research contents of this paper include the following aspects:?1?Base on structural property of natural soft clay and the phenomenon that the seepage in soft clay may deviate from Darcy's flow law under low hydraulic grade,the governing equation of nonlinear consolidation of structural soil with Hansbo's non-Darcian flow was developed to considering time-dependent loading,and the numerical solution of this equation was given.The reliability of differential program was verified by means of the result of contrast calculation in the condition of q_p=0 or c_c1=c_c2 with the calculation results of Ignoring soil structure and by comparing the calculation results in the condition of m=1 with the calculation results of Darcy's law.Finally,based on the reliability of numerical solutions,the influences of the non-Darcian flow,the difference of structural yield stress and the soil gravity stress,the compression index when the structural yield stress was greater than the effective stress,the loading rate and the permeability index on nonlinear consolidation behaviors of structural soil was analyzed in detail.?2?The nonlinear consolidation control equation of strong structural soil with Hansbo's non-Darcian flow was developed to considering instantly loading,and the finite difference method was used to obtain the numerical solution of the equation.The reliability of differential program was verified by means of the result of contrast calculation in the condition of T_vc=0?q_p=q_d with the calculation results in the condition of T_vc=0 in the previous chapter.Finally,based on the reliability of numerical solutions,the influences of the non-Darcian flow,the difference of structural yield stress and the soil gravity stress,the difference of turning stress and the soil gravity stress,the compression index when the structural yield stress was greater than the effective stress and the ratio of the permeability index to the compression index when the stress is greater than the twist stress effectively on one-dimensional nonlinear consolidation behavior of strong structural soil with Hansbo's non-Darcian flow was analyzed in detail.?3?Considering time-dependent loading in actual engineering,one-dimensional nonlinear consolidation theory structural soil with non-Darcian flow was systematically analyzed,and the finite difference method was used to obtain the numerical solution of the equation.The reliability of differential program was verified by means of the result of contrast calculation in the condition of qp=qd with the calculation results in the second chapter.Finally,based on the reliability of numerical solutions,the influences of the non-Darcian flow,the ratio of the permeability index to the compression index when the stress is greater than the twist stress effectively,the difference of structural yield stress and the soil gravity stress,the difference of turning stress and the soil gravity stress and the loading rate on consolidation behavior of strong structural soil with Hansbo's non-Darcian flow was analyzed in detail.