Bearing Capacity of Ring Footing on Geogrid Reinforced Sand

Abstract

This research deals with the analysis of bearing capacity of ring footing on geogrid reinforced sand experimentally. The effect of variation of many parameters on the bearing capacity were studied such as, (number of geogrid layers(N) ,depth ratio of the topmost layer of geogrid(u/Do), the vertical distance ratio between consecutive layers(h/Do), depth of embedment ratio of footing(Df/Do), relative density of sand and the ring diameter ratio(Di/Do). Also, the effect of variation of each parameter on the others had been studied. In general, the results showed that by increasing the ring diameter ratio Di/Do , the bearing capacity increases until it reaches the value of (Di/Do=0.4) then after this point when the Di/Do increases the bearing capacity decreases .Increasing the number of reinforcement layers (N), increases the bearing capacity. When the depth of embedment (Df/Do) increases the optimum number of reinforcement layer (N) decreases. The optimum value of reinforcement layers was (N=4) for (Df/Do=0) and (N=3) for (Df/Do=0.5 and 1). The optimum depth ratio of the topmost layer geogrid was (0.5-0.53Do). The optimum vertical distance ratio between consecutive layers was (0.51-0.53Do) for two layers of reinforcement and it was (0.25Do) for three and four layer of reinforcement. The ring diameter ratio (Di/Do), Depth of embedment ratio (Df/Do) and relative density have no direct effect on the depth ratio of topmost layer or the distance between consecutive layers. Also, the depth of embedment ratio of footing was (0Do, 0.5Do, Do) and ring diameter ratio (Di/Do) was (0, 0.3, 0.4, and 0.5)