Bearing capacity of strip footings supported on geocell-reinforced sand

This paper presents the results from laboratory-model tests on a strip footing supported by a sand bed reinforced with a geocell mattress. The parameters varied in the testing program include pattern of geocell formation, pocket size, height and width of geocell mattress, the depth to the top of geocell mattress, tensile stiffness of the geogrids used to fabricate geocell mattress and the relative density of the sand. With the provision of geocell reinforcement, failure was not observed even at a settlement equal to 50% of the footing width and a load as high as 8 times the ultimate bearing capacity of the unreinforced sand. Based on the model test results, the depth of placement and the dimensions of the geocell layer for mobilising maximum bearing capacity improvement have been determined. In addition to the tensile strength of reinforcement, the aperture size and orientation of ribs of the geogrid used to fabricate geocell mattress must be taken into account while evaluating its contribution to the improvement in the performance. (C) 2001 Elsevier Science Ltd. All rights reserved.