One-dimensional thermal consolidation analysis of saturated clay with variable compressibility and permeability considering partial drainage boundaries

Abstract

The nonlinear consolidation characteristics of saturated clay will be markedly impacted by temperature. However, despite the ample progress of calculation methods for the one-dimensional consolidation of soft ground, theoretical investigations into thermal consolidation have not been thoroughly explored. Moreover, partially drained boundary is more consistent with the engineering practice, which is imperative to be involved to mitigate computational error when determining the consolidation behavior. In this context, a mathematical model is established to incorporate the temperature-dependent nonlinear characteristics of compressibility and permeability. Subsequently, the resulting governing equations and numerical solutions for the one-dimensional nonlinear thermal consolidation of saturated clay are obtained under partial drainage boundaries. Then the accuracy and reliability of the proposed model are validated by degradation analysis and simulation analysis with good agreements. Furthermore, the computed results of current study are adopted to conduct an in-depth assessment of the influence of several crucial parameters on the nonlinear consolidation behavior. The results demonstrate that increasing the temperature can remarkably accelerate the dissipation rate of excess pore water pressure, thereby promoting the consolidation process of saturated clay. The inclusion of partial drainage boundaries also has a significant influence on the consolidation performance, with a maximum difference in the dissipation rate of excess pore water pressure reaching up to 40 % when transforming a completely drained boundary into a completely undrained boundary. Additionally, the increment of pre-consolidation pressure will induce a gradual acceleration of consolidation rate.