Behavior of repeatedly loaded rectangular footings resting on reinforced sand

The paper presents a laboratory study of the effect of geosynthetic reinforcement on the cumulative settlement of repeatedly loaded rectangular model footings placed on reinforced sand. Repeated load tests were carried out with different initial monotonic load levels to simulate structures in which live loads change slowly and repeatedly such as petroleum tanks and ship repair tracks. Three series of tests were carried out. Tests of series 1 were performed to determine the ultimate monotonic bearing capacity. Tests of series 2 were performed on unreinforced sand under vertical repeated loads. Tests of series 3 were performed to study the effect of sand reinforcement on the footing response under the same loads. The studied parameters include the initial monotonic load levels, the number of load cycles, and the relative density of sand along with geosynthetic parameters including size and number of layers. Both the ultimate bearing load and the cumulative settlement were obtained and analyzed.