Soil Structure Interaction Using Silt Clay by Direct Shear Test: A Review Paper

Direct shear test is a type of laboratory test which is used to determine shear strength parameters such as cohesion c (kPa) and angle of internal friction φ (°). For performing this test various conditions should be considered. The conditions are such that there must have constant vertical pressure at the top of the sample and the volume of the sample must be constant to estimate shear strength parameters of loose and dense soils. A constant horizontal displacement rate is utilized to determine shear strength parameters. The researchers also found some factors which control these shear strength parameters. These controlling factors are surface roughness, soil composition, the magnitude of normal loading, and moisture content. In the direct shear test, the surface thickness of the sample influences shear strength parameters. The researchers have given a different report based on their analysis. They showed the different modes of shear strength parameters in different conditions of sand, clay, soil, etc. for the interaction of soil structure. By mixing geo-membrane, geotextile, etc. with soil, sand, clay greatly affects shear strength parameters. When horizontal displacement is applied, vertical deformation of the shear plane of soil increases up to the yielding point of sand. The direct shear box contains a gap between the upper and lower ring but it is not constant. But, there are some drawbacks to their research. They did not show how shear strength parameters behave in silty clay. In this paper, a relative review of soil-structure interaction using silty clay is shown. In the direct shear test, cohesion is increased due to an increase in moisture content. To determine shear strength parameters, the conditions of silty clay are unsaturated. For this investigation, a shear box is used. Different loading is applied to see the deflection in a specific time interval.