Journals Proceedings

Abstract

This paper describes a series of the plate load tests performed in a test pit measuring 2000×2000 mm in plane and 700 mm in depth. To simulate traffic loadings, fifteen loading and unloading cycles were applied to the loading plate with amplitudes of 400 and 800 kPa. The optimum depth of the top most layer of geocell and the optimum vertical spacing of geocell layers, based on plate settlement, are both approximately 0.2 times loading plate diameter. The results show that installation of the geocell layers in the foundation bed decreases the accumulated plastic and total settlements of loading plate, in addition to increase its elastic settlement. Efficiency of geocell reinforcement was decreased by increasing the number of the geocell layers for all applied stress levels and number of cycles of applied loading. The results of the testing reveal the ability of the multiple layers of geocell reinforcement to ‘shakedown’ to a fully resilient behavior after a period of plastic settlement except when there is little or no reinforcement and the applied cyclic pressure are large. When shakedown response is observed, then both the accumulated plastic settlement prior to a steady-state response being obtained and the resilient settlements thereafter are reduced. The results depicted that the use of four layers of geocell respectively decreases the total and residual plastic settlements about 53% and 63% and increases the resilient settlement of 145% compared with the unreinforced case.