Experimental and Numerical Investigation of Load Carrying Capacity of Vertically and Horizontally Reinforced Floating Stone Column Group

The present work investigates the load carrying capacity of vertically and horizontally reinforced floating stone column group through model testing. Two group arrangements using three and four stone columns for both unreinforced and reinforced conditions are testing under compressive loading. The geotextile reinforcement is provided throughout the stone column length (300 mm) in vertical direction and in form of circular discs at spacing of 30 mm along column length for reinforcing horizontally. The results of load-settlement behavior and failure mechanism of both unreinforced and reinforced group is studied. The testing results indicated reduced lateral bulging and higher stone column load capacity for horizontally reinforced columns in comparison to vertically reinforced. For validation of experimental results, numerical modeling using finite element (FE) code Plaxis 2D has also been conducted. The FE results depict lower load capacity as compared to model testing for settlement of 30 mm. However, the failure mode for both model tests and FE analysis was marked by bulging near the top of stone column and punching. Furthermore, load capacity is also check using empirical relations as given by IS code and previous literature. It is observed that experimental and analytical results are found in good agreement.