Experimental analysis of reinforcement methods for stone column foundations

Geosynthetic-reinforced stone columns can significantly improve weak foundations. While previous studies have focused on the individual effects of vertical or horizontal reinforcement, the combined influence of both on stone column foundation performance remains poorly understood. Through physical model tests, this study investigated the effects of various reinforcement methods on the bearing capacity and deformation characteristics of stone column foundations, with a particular focus on the combined reinforcement in enhancing their performance, addressing this research gap. This study encompasses different enhancement lengths, horizontal reinforcement spacings, and combinations of reinforcement methods. Experimental results demonstrate that geosynthetics significantly limit radial deformation and improve the bearing capacity of stone column foundations. Notably, the bearing capacity increases with reduced reinforcement spacing and extended enhancement length. Among all the reinforcement types tested in this study, the full-length (L) vertical reinforcement demonstrated the most significant impact. Additionally, the study examines stress transfer and lateral stress distribution within the stone columns, revealing that as the load increases, the stress ratio at the stone column base and lateral stress rises, with lateral stress peaking at a depth of 2.5D from the surface. This behaviour aligns with the deformation patterns observed in the model tests.