Use of Coir Geotextile (CG) over Black Cotton (BC) soil during Rural Road Construction

Abstract

      Transportation adds to a country's overall growth and therefore plays a critical role in its advancement. As India is largely rural in nature, road connections have distinct advantages over other connectivity modes. Economy, time, environmental restrictions, and many other variables, however, make the task of a highway specialist more complex to provide its users with a healthy and cost-effective road network. One of the major problems faced by the engineers during highway construction in rural areas of India is the presence of Black Cotton (BC) soil at ground level. It is inorganic clay having medium to high compressibility, high shrinkage and swelling nature, extremely hard when dry, however lose its strength totally when in wet condition. Because of wetting and drying process, here there is a chance of pavement failure resulting into settlement, unevenness and cracking. The lacuna identified with the traditional approach commands the problem to be tackled at its rudimentary level by rectification of the basic weakness of the formation subgrade and to settle for a strategic solution. Coir Geotextiles (CG) are used to increase the efficiency of roads on such soils, serving as reinforcement. It is noted that with the application of the Coir Geotextile (CG) layer beneath the Granular Sub Base (GSB) layer, due to intermittent changes in moisture content in expansive and shrinkable soil, it will be useful to reduce the time of upper layers of road pavement. A systematic plan for executing the layer thought the construction has been proposed in the paper.