Study on Uplift Behaviour of Plate Anchor in Geogrid Reinforced Sand Bed

Two series of pullout loads tests were conducted on anchors embedded in submerged sand in this study. First series of tests were in submerged sand and the second series of test were in submerged sand reinforced with single layer of geogrid. The geogrid was positioned directly on the anchor and its width ratio was varied (Br/B = 2, 3 and 4). Other parameters varied in both monotonic and cyclic mode of loading were embedment ratio of anchor (H/B=2, 3 and 4) and density of sand (loose, medium and dense conditions). All the cyclic load tests were conducted for the cyclic load ratio of 60%. From the results of study it was found that the load - displacement response of unreinforced and reinforced sand for a given density and depth of embedment are similar except higher peak and residual loads due to the inclusion of geogrid reinforcement. Both peak and residual pullout loads increased with width ratio of reinforcement for the densities and embedment ratios studied in this investigation. In the case of cyclic load, the displacement of anchor was increased with decreasing rate and reached almost a constant value after 350 cycles. The post cyclic peak pullout load was marginally higher than the peak pullout load of monotonic condition for all the comparable test conditions.