Increase the Shear Strength of Soil by Partial Replacement of Fly Ash

Abstract

Soil is the foundation for any civil engineering structures. It is required to bear the loads without failure. In some places, soil may be weak which cannot resist the oncoming loads. In such cases, soil stabilization is needed, numerous methods are available in the literature for soil stabilization. In this study, fly ash was mixed with clay soil to investigate the relative strength gain in terms of Vane shear test, Specific gravity test, Plastic & liquid limit test, C.B.R. test and Compaction test. The tests were performed as per Indian Standard specifications. The following materials were used for preparing the samples: Soil sample, Fly ash. The soft clay used for these experiments was brought from a site, near between Hostel number 2 to main building of R.V.S.C.E.T., Jamshedpur, Jharkhand. The physical properties of the soil were determined as per IS specifications. Fly ash for the study was brought from T.T.P.S., Lalpania, Bokaro, Jharkhand. It is finely divided residue resulting from the combustion of ground or powdered coal from electric generating plants. It has high water absorption capacity. In this test programme, without additives the sample was tested to find the optimum moisture content, C.B.R. value, vane shear value, plastic &liquid limit value and specific gravity value and the same procedure was repeated two times with various percentage (20% and 30%) of fly ash. The fraction for which maximum strength is obtained was found out.