Improvement of Shear Strength of Black Cotton Soil Using Polyester Fibers

Abstract

Construction of building and other civil engineering structures on available clayey soil is highly risky on geotechnical grounds due to poor strength properties of the clayey soil. There may be the need for soil treatment to improve the engineering properties of soil. In practice admixtures with fly ash, lime and geogrids are used frequently to stabilize soils and improve their strength properties. Polyester fibers have been extensively used in civil engineering applications for many years. These fibers are used in concrete as a three dimensional secondary reinforcement. The influence of randomly oriented polyester fiber on the engineering behaviour of soil has not been reported to the same extent. Ease of application and reduction in cost are making this treatment more popular. The purpose of this investigation is to identify and quantify the influence of fiber variables (content and length) on performance of fiber reinforced soil specimens. In this study polyester fibers were mixed with clayey soil in various proportions (0%,0.25% 0.50%, 0.75%, and 1.0% by weight of dry clayey soil) to investigate the relative strength gained in terms of unconfined compression . It was found that strength properties of clayey soil increases with the inclusion of fibers up to 0.75%.