在土中渗流遵循指数形式渗流定律下,假定土体压缩系数和渗透系数在固结过程中均保持不变,在拉格朗日坐标系下,以超静孔隙水压力为变量,建立软土一维大变形固结问题的控制方程及求解条件.利用有限差分法,对计算模型进行求解,得到超静孔隙水压力的数值解答.在此基础上,对某时刻不同深度处土体孔隙比以及地基沉降变形进行求解,并据此给出按变形定义的地基平均固结度和按应力定义的地基平均固结度的解答.最后,结合实例分析了渗流指数对大变形固结性状的影响,分析了基于指数形式渗流定律的软土一维大、小变形固结理论的区别,给出了基于指数形式渗流定律的软土一维固结问题中必须要考虑大变形特性的条件.
Abstract : According to the exponential flow law for soft clay and the constant coefficients of compressibi lity and permeability during consolidation, the equations and solution conditions of onedimensional large strain consolidation were established in Lagrangian coordinates with excess pore water pressure as varia ble. The computation module was solved by finite difference method to obtain the numerical solutions for pore water pressure. The numerical solutions of void ratio with different depth and settlement of founda tion at certain time were solved, and the average consolidation degrees in terms of deformation and stress were both provided. The influence of exponent m on large strain consolidation behavior was analyzed by numerical examples. The difference of consolidation theory with exponential flow law between small strain and large strain was analyzed, and the condition that large strain must be considered in onedimensional consolidation of soft clay with exponential flow law was provided.