Deformation characteristics of a steel cylinder-backfill-stone column combined revetment system under surcharge

The deformation of a steel cylinder-backfill-stone column combined revetment system under a 300 kPa surcharge is analysed, integrating centrifugal model testing and numerical simulation, with particular focus on the steel cylinder displacement, ground settlement and the stone columns displacement. Furthermore, a systematic parametric analysis was conducted to investigate the key parameters governing the combined revetment system. Revealed that combined revetment system exhibits a synergistic deformation mechanism under surcharge loading, governed by the reconstruction of stress transfer pathways, the increase in the equivalent stiffness of the foundation, and structural boundary constraints. The displacement at the cylinder top initially decreases and then stabilizes with increasing surcharge distance, indicating the existence of a critical surcharge distance. The presence or absence of stone column reinforcement in soft ground produces a significant difference in the deformation behaviour of the combined revetment system. Ground settlement and horizontal displacement are strongly influenced by the location of the stone columns. This deformation behaviour reflects a close coupling mechanism of the combined revetment system.