Deformation and load transfer of pile-supported foundation reinforced with soilbags raft cushion

This study proposes a new pile-supported soilbags raft cushion for foundation treatment. A series of twodimensional model tests were conducted on the reinforced foundation to investigate its deformation and load transfer characteristics. An analytical method was established to determine the surface pressure between the piles. The tests demonstrated that the soilbags raft cushion can reduce the differential settlement of the foundation by improving the uniformity of the load transfer. The deformation patterns and load transfer efficiency of the soilbags raft cushion reinforced foundation were found to be related to the pile spacing, the embedded depth of the pile top, the thickness of the soilbags raft cushion, and the external pressure applied to the foundation surface. The performance of soilbags raft cushion is more effective when the ratio of the embedded depth of the pile top to the pile spacing is at least one and the ratio of the thickness of the cushion to the embedded depth of the pile top is at least 0.2. The analytical method considers the relative pile-soil settlement and the elastic modulus of the soilbags raft cushion reinforced foundation, allowing for a reasonable evaluation of the surface pressure between the piles and the load transfer efficiency.