Influence of coupling effect in the chemo‐hydro‐mechanical consolidation of saturated soil layer

Abstract

In geological sites containing chemical pollutants, the clay buffer layer (CBL) is frequently utilized to isolate the pollutants from the external environment. Moreover, hydraulics, mechanics, and chemistry jointly pose impacts on the consolidation of CBL and the diffusion of chemical substances. In order to consider the coupled effect (termed chemo-hydro-mechanical-CHM), a one-dimensional consolidation model that fully considers CHM coupling (such as convection, ultrafiltration, and osmotic efficiency) is established. In the developed model, the excess pore pressure, chemical concentration, and soil settlement during the consolidation process are calculated via finite Fourier transform and inverse transform. Finally, the CHM coupling effect on consolidation under different conditions is analyzed and discussed. The results indicated that the coupling effect slowed down the entry of chemical substances into the soil layer so that the excess pore pressure dissipated faster, and the negative pore pressure was larger. Furthermore, the coupling effect increased the maximum settlement during consolidation but did not change the final settlement. The coupling effect prolonged the time of consolidation. In addition, the higher the osmotic efficiency, the greater the coupling effect, but the osmotic efficiency did not affect the time of consolidation.

Semi‐analytical solution for a simplified 1D chemo‐hydro‐mechanical model in fluid‐saturated viscoelastic clay

“…Zheng et al 52 investigated the 1D CHM model in an elastic soil and discussed the influence of coupling effect. By applying η = 0, the model presented in this study is simplified to the simplified CHM model of elastic soil.…”

“…By applying η = 0, the model presented in this study is simplified to the simplified CHM model of elastic soil. The physical parameters used in Zheng et al 52 are listed in Table 1. The excess pore-fluid pressure, solute concentration, and displacement obtained via these parameters were compared with those in Zheng et al 52 The result is shown in Figure 2.…”

“…The physical parameters used in Zheng et al 52 are listed in Table 1. The excess pore-fluid pressure, solute concentration, and displacement obtained via these parameters were compared with those in Zheng et al 52 The result is shown in Figure 2. It can be seen that when η = 0, the solutions of the present model agree well with those of the elastic model.…”

“…It can be seen that when η = 0, the solutions of the present model agree well with those of the elastic model. 52 In other words, when η = 0, the present model is simplified to an elastic model.…”

Non‐Darcian flow toward an injection well fully penetrating a leaky confined aquifer with clogging‐induced permeability reduction

“…Generally, the Laplace transform is more commonly used to solve the model of well hydraulics for both CRR and CHR tests. 21,[27][28][29][35][36][37][38][39] However, the transform from the physical domain to the Laplace domain can be rather difficult or even impossible because of the including temporally variable permeability function. For this reason, the Hankel transform with the v-th order was applied with respect to 𝑟 ′ for the case of CRR.…”