考虑Hansbo渗流和连续排水边界的双层软土地基一维非线性固结

One-dimensional Nonlinear Consolidation of Double-layered Soft Soil Foundation Considering Hansbo’s Flow and Continuous Drainage Boundaries

摘要:

引入Hansbo非达西渗流模型和非线性压缩关系，建立了线性荷载作用下、考虑连续排水边界条件的双层软土地基一维非线性固结模型，并采用隐式有限差分法进行数值求解。数值分析表明，双层地基中Hansbo渗流参数取值越大，土体的沉降速率就越慢；当下层土与上层土的初始压缩系数比值较大时，孔压消散速率减慢，导致地基沉降速率降低；当下层土和上层土的初始渗透系数比值增大时，上层土的孔压消散速率减慢。此外，尽管较大的初始渗透系数比值会增大土体沉降速率，但对最终沉降量无明显影响。

Abstract:

The Hansbo’s non-Darcian flow model along with a nonlinear compression relationship was introduced to derive a one-dimensional nonlinear consolidation model for a double-layered soft soil foundation under linear loading while considering continuous drainage boundary conditions. An implicit finite difference method was subsequently employed for numerical solution. Numerical analyses indicate that， in the double-layered foundation， an increase in the Hansbo’s flow parameters will lead to a reduction in the rate of soil settlement. If the ratio of initial compression coefficients of the lower soil layer to the upper soil layer is large， the dissipation rate of pore pressure slows down， resulting in a decrease in the settlement rate of the foundation. Furthermore， an increase in the ratio of the initial permeability coefficients of the lower soil to the upper soil results in a slower dissipation rate of pore pressure in the upper soil. In addition， although a larger initial permeability coefficient ratio increases the soil settlement rate， it does not have a significant impact on the final settlement.