Clayey soils exhibit high shrinkage and compressibility characteristics as well as low shear strength. Engineering projects in clayey soils requires construction of deep foundations or use of ground improvement techniques. Soil reinforcement is a popular and widely used ground improvement technique. Shallow foundations resting on geosynthetics reinforced sand layer is a cost effective and feasible construction technique. Since the geosynthetics are placed in sand or granular layer compaction can be easily performed to achieve the design density and adequate friction between sand and the geosynthetics. The performance of strip footings resting on geosynthetics reinforced sand layer overlying clay layer is investigated using finite element software MIDAS GTS NX. A number of numerical models were analyzed and the effect of various parameters such as type of geosynthetic material, depth of sand layer, critical depth of reinforcement below base of footing, number of reinforcement layers, spacing between multiple layer of reinforcement and width of reinforcement layer on the load-settlement behavior of strip footings was studied. The optimum values of these parameters were also determined. Laboratory models of clay underlying sand layer with and without geosynthetics reinforcement were prepared in a steel tank of size 84 * 25 * 50 cm and monotonic load was applied through a steel plate of width 8 cm up to failure. The model test results were compared with the finite element analysis results. Design charts were developed which can be used to determine the depth of sand layer and number of reinforcement layers for a target bearing capacity.
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