This Paper demonstrates the evaluation of deformation and pressure distribution below a layer of load bearing geocells on subgrade, considering a two-layered system. The proposed method evaluates deflections at the interface of the geocell and the subgrade, the deemed two layers. The objective essentially includes determination of the spatial extent to which geocells are effective below a load. The Authors have extended Huang’s analysis for a two-layered system to determine vertical pressures at the interface and the distance at which the pressures due to imposed loads die out. The proposed technique does not require any sophisticated analytical tools or software other than Huang’s curves based on the extension of Burmister’s Two Layer elastic theory. When a vertical pressure over a limited area is applied onto a geocell panel, a wide-angle load spread has been observed by several researchers and geocell organizations through field and laboratory tests. The geocell panel develops its rigidity through infill of congruous geocells as well as the vertical curvilinear geocell walls, rhomboidal in plan. The composite structure is complex for analyses by conventional mechanics. Furthermore, the modulus of a non-plastic soil significantly improves when it is infilled within the confines of a geocell system. This improvement, cited as “Modulus Improvement Factor”, MIF is evaluated by computing the improved E value from conventional cyclic plate load tests on infilled geocell layer at the project site. Such modulus improvement enhances the performance of the geocell-subgrade system.
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