ABSTRACT
Geocells have been used as basal reinforcement in improvement of foundation soils, embankments and highway subgrades to increase bearing capacity and reduce total and differential settlements. Attempts have been made in engineering practice to somehow reduce the extensibility of the geocells whenever they are subjected to considerable tensile forces. This paper presents pullout test results on conventional (ordinary) and diagonally enhanced geocells under different surcharge pressures to evaluate feasibility of their applications when subjected to significant planar forces. Extensive pullout tests on scaled geocells embedded in silica sand are performed to investigate the effects of improvements on load-deformation response, strength and stiffness. Conventional web-shaped geocells are having a small stiffness when subjected to planar tension attributed to deformability of webs. Therefore, conventional geocells may not function properly when subjected to tensile forces along the main plane in service. A special geocell is fabricated in this study, similar to tendoned geocells, through adding diagonal members along the induced tensile load to overcome the shortcomings of conventional geocells. The test results have shown that both the stiffness and ultimate resistance of the diagonally enhanced geocells have significantly improved with respect to the conventional ones.
