Large-Strain Consolidation Model for Soft Soils Treated with Air-Boosted Vacuum Preloading: Analytical and Numerical Solutions

As an emerging soft soil improvement technology, air-boosted vacuum preloading accelerates consolidation by enhancing the horizontal pressure differential between vertical drains and surrounding soils. Studies have shown that the large-strain and nonlinear consolidation characteristics of highly compressible soft soils significantly influence consolidation behaviors. However, the theory of large-strain consolidation for soft soils treated with air-boosted vacuum preloading, considering both nonlinear compression and rebound recompression, has rarely been reported in the literature. In this study, analytical and numerical solutions for nonlinear large-strain consolidation of soft soils with vertical drains treated by air-boosted vacuum preloading were established. The applicability of the developed consolidation model for practical soft soil treatment was verified by comparing it with existing analytical and numerical consolidation models, as well as measured data. Parametric sensitivity analyses evaluated the effects of air-boosted pressure, time-dependent well resistance, and drain spacing ratio on consolidation behavior.