A numerical solution for nonlinear large-strain consolidation of soils with #br#
vertical drains by considering time-and depth-dependent well resistance
LI Kuo，LI Chuanxun
(Faculty of Civil Engineering and Mechanics，Jiangsu University，Zhenjiang，Jiangsu 212013，China)
Abstract：The soft soil with high compressibility has typical geometric and material nonlinearities. However，the solutions for the large strain consolidation of soils with vertical drain，in which the time-and depth-dependent well resistance are considered，are rarely reported in the literature. Considering the nonlinear compressibility and permeability，and the time-and depth-dependent well resistance，a large-strain nonlinear consolidation model of soils with vertical drain is established in the Lagrangian coordinate system，in which the excess pore water pressure serves as a variable. The numerical solution for this consolidation model is derived by the finite difference method. The numerical results are compared with the existing small-strain analytical solution and large-strain numerical solution for the vertical drain ground to verify the correctness of the presented method. Then，the consolidation behavior analysis of the large-strain consolidation of soils with vertical drains under different conditions is performed，and the results show that the space-time variation of well resistance significantly reduces the consolidation rate. The time-dependent well resistance has a greatly impact on the consolidation rate. However，the final settlement of vertical drain ground can not be affected by the time-and depth-dependent well resistance. The consolidation rate under the uniform distribution of initial effective stress is less than that under the linear distribution. The final settlement values of the vertical drain ground in the two cases are not equal，and the differences between the two settlement curves are greatly large. The assumption that the discharge capacity flowing into the vertical drain at any depth are constant results in the faster consolidation rate，and overestimates the actual consolidation rate of the vertical drain. The promotion effect of vertical flow on the consolidation of vertical drain decreases as the ratio of the length to the influential radius of drains increasing.
李 阔，李传勋. 考虑井阻随时空变化的竖井地基大应变非线性固结分析[J]. 岩石力学与工程学报, 2023, 42(S1): 3743-3754.
LI Kuo，LI Chuanxun. A numerical solution for nonlinear large-strain consolidation of soils with #br#
vertical drains by considering time-and depth-dependent well resistance. , 2023, 42(S1): 3743-3754.
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2023, Vol. 42 
