Performance of geosynthetics-strengthened unconnected piled raft foundations under seismic loading

Over the past 20 years, geosynthetic reinforcement has been widely used in earthen constructions. For constrained building projects and challenging ground conditions, geosynthetic-reinforced-pile-supported (GRPS) embankments are regarded as dependable options. There has been significant research into ways to improve the stability of pile foundations, and there has also been some research into the viability of using unconnected piled raft under seismic load. This study investigates the use of geosynthetics to improve the performance of unconnected pile foundations under seismic load. A series of reduced-scale physical model experiments conducted on a shaking table was used to assess the seismic soil-structure interaction behaviors of geosynthetics-reinforced pile foundation systems. The study makes use of disconnected, closed-end aluminum piles with different thicknesses of cushion layers of sand soil and different spacing between piles are used in the study. The performance of disconnected footing was examined using a shaking table to determine the impact of the geosynthetics reinforced. These model findings are used to identify and thoroughly describe the contradictions in the present design methodologies. This study shows the settlement of the foundation under seismic loading decreased by reinforcing the cushion layer with one and two layers of geogrid materials, increasing the thickness of the cushion layer led to increasing the settlement of the foundation under seismic loading, where the settlement decreases with decreasing the value of spacing between piles. However, with further increases in either the cushion thickness or cushion stiffness or both, the effect of improvement would decrease.