Evaluation of the Effects of Reinforced or Stabilized Coarse Surface Layer on Bearing Capacity of Soft Clays

Natural soft clay soils due to the lack of sufficient bearing capacity and the high deformation potential require to be improved using either chemical stabilization methods or physical methods such as soil reinforcement or pre- compression. The method used is greatly influenced by technical and the economic considerations as well as the physical characteristics required (Abdi and Zandieh, 2014). Chemical stabilization generally results in increasing the strength and the bearing capacity and reduces the swelling- shrinkage potential of the clayey soil. On the other hand from ancient times humans have used natural fibers to alleviate the weakness of soil in resisting tensile stresses (Abu-Farsakh et al., 2008). Now-a-days due to the technical progress made synthetic materials such as geo-synthetics are used for soil improvement. Use of geo-synthetics such as geogrids and geotextiles have grown rapidly in the construction of soil structures such as embankment dams for reducing the volume of materials needed as well as drainage purposes, increasing bearing capacity in foundation engineering, etc (Alawaji, 2001). These materials are easy to use and environmentally friendly. Coarse grained materials are also employed in construction of reinforced soil structures due to high drainage and shear strength characteristics as well as volume stability due to moisture variations and time (Alawaji, 2001).