To investigate the one-dimensional nonlinear consolidation characteristics of a double-layer foundation under multi-stage loading, a one-dimensional nonlinear consolidation equation for the double-layer foundation was established, and numerical solutions were obtained through the finite difference method. The accuracy of the proposed solution was validated by comparing it with existing analytical solutions and finite element analysis results. Based on these comparisons, the influence of nonlinear parameters, double-layer soil properties, and loading conditions on the consolidation behavior of the double-layer foundation was further examined. The results indicated that, under multi-stage linear loading conditions, an increase in the initial permeability coefficient ratio of the double-layer foundation resulted in a significant reduction in excess pore water pressure and an acceleration of consolidation. The compression index was found to predominantly affect the later stages of consolidation, with minimal impact on the early stages. The consolidation rate was observed to increase as the permeability coefficient ratio decreased. Despite notable differences in early consolidation behavior under varying loading conditions, the findings reveal that these discrepancies are alleviated in the later stages, ultimately resulting in no significant overall difference in the time required for the foundation to achieve complete consolidation.

来源平台：EUROPEAN JOURNAL OF ENVIRONMENTAL AND CIVIL ENGINEERING