Precise Model for Predicting Excess Pore-Water Pressure of Layered Soils Induced by Thermal-Mechanical Loads

摘要

This paper proposes a precise model to investigate the time-dependent response of excess pore-water pressure in stratified saturated soil induced by coupling effects from temperature and mechanical load based on the Laplace-Hankel transform and the precise integration method (PIM). First, the partial differential equations for the thermal consolidation problem are transformed into the ordinary equations by the integral transform techniques. By combining the adjacent layer elements and considering the boundary conditions, the extended precise integration solutions to the thermal consolidation problem in the transformed domain are deduced. By applying the corresponding integral inverse transforms, state variables in the physical domain are obtained. The existing analytical solutions and model test results validate the presented model. Additionally, numerical examples explore the influence of temperature load, Young's modulus, and permeability coefficient on the thermal consolidation behavior. Numerical results reveal that (1)thermal load has a significant influence on the peak values of excess pore-water pressure and gives rise to the Mandel-Cryer effect; (2)due to the slower velocity of heat conduction than of pore-water penetration, the dissipation time of excess pore-water pressure caused by thermal-mechanical loads lags behind that of the mechanical load; and (3)the layering behavior of soils has significant effects on the distribution of excess pore-water pressure and the consolidation process.