Drained Cavity Expansion Analysis with a Unified Hardening Model for Clays and Sands

This study presents a novel semi-analytical solution for the drained expansion of cylindrical and spherical cavities with a unified hardening model for both clays and sands. The three-dimensional strength of soils is considered by the spatially mobilized plane (SMP) criterion. Large-strain analyses are incorporated into the developed cavity expansion solution to obtain the entire stress-strain histories of soils in plastic regions. By formulating the problem as an initial value problem in the Lagrangian scheme using an auxiliary independent variable, the present study solves the problem numerically. A thorough parameter analysis is conducted for both cylindrical-spherical cavities in clay and sand scenarios, and the results are compared with other existing solutions to demonstrate the distinctive attributes of the present solution. It is found that the present solution can effectively capture the evolutionary process of both strength and overconsolidation characteristics of soils, as well as the contraction and dilation behaviors of soils. Sensitivity analyses revealed that λ, κ, overconsolidation ratio, and e0 exerted a more substantial influence on soil response compared to other parameters. The proposed solutions are ultimately applied to a centrifuge cone penetration test conducted on models of dry Toyoura sand. The results demonstrate strong agreement with measured data, highlighting the good performance of the proposed cavity expansion solutions in engineering applications.