Analytical modeling and experiments on soft soil consolidation with vacuum preloading-airbag pressurization

This study aims to provide substantial theoretical support for employing vacuum preloading-airbag pressurization (VP-AP) to enhance soft soil foundations. By integrating the airbags and prefabricated vertical drains (PVDs) within the analytical framework, the consolidation models are developed to accommodate double smear zones and well resistance. Analytical solutions for various airbag pressurization scenarios are derived under the equal-strain assumption. A model test is subsequently conducted to investigate the settlement process of soft soil using the VP-AP method. The validity of the proposed theoretical model is corroborated through comparison with existing analytical solutions and experimental data. The accuracy of the predictive model is further substantiated by the model test results. Lastly, this research offers an in-depth analysis of soil consolidation behavior under diverse influencing factors. The findings indicate that the VP-AP method demonstrates superior efficacy over conventional vacuum-surcharge preloading when the airbag pressure matches the external load pressure. Additionally, an increase in the radius of airbags enhances the soil consolidation efficiency. The analytical model presented in this study elucidates the consolidation mechanisms of the VP-AP method, with experimental research confirming the efficacy of this approach and the predictive model established herein.