Finite element analysis of clay reinforced with geogrid encapsulated in thin layers of sand

Reinforced Granular Beds are often used to support foundations on weak soils and low lying areas. But now granular soils have become very scarce and it makes reinforced soil technique uneconomical. The cost effective option is to reinforce the locally available soil with suitable geosynthetics. But the effectiveness of reinforcement embedded in clayey soil is very less when compared with granular soil. This paper investigates the possibility of reinforcing the locally available clayey soil with geogrid encapsulated in thin layer of sand by carrying out a series of finite element analyses using the software PLAXIS 2D. The parameters studied are the effects of thickness of thin granular layer and its depth below the base of footing. The results of the finite element analyses indicate that bearing capacity of clay can be improved considerably by reinforcing with geogrid embedded in thin layer of sand. It is observed that the normal and shear stresses at the interface between sand and clay are considerably influenced by the thickness of sand layer.