Transport sector accounts for a share of 6.4 per cent in India’s Gross Domestic Product (GDP). Road transport has emerged as the dominant segment in India’s transportation sector, with a share of 5.4 percent in India’s GDP. Hence taking steps to increase the life of pavements is an absolute necessity to maintain the growth of transportation in India. Owing to India’s s trategic location near the equator, the roads here face drastic conditions wherein they undergo phases of alternate wetting and drying which ultimately reduce the life of flexible pavements. This project investigates the effect of alternate wetting and drying on coir reinforced SMA. Optimum bitumen content and optimum fiber content were estimated using Marshal Method of Mix Design and their performance was analyzed with respect to virgin mix. To study the effect of alternate wetting and drying on the pavemen ts’ performance, the samples were conditioned with alternate wetting and drying cycles, and were tested for indirect tensile strength and wheel rut. It was observed that upon addition of coir fibre, the drain down and rutting properties improved and the tensi le strength of the mix increased. A higher rate of pavement deterioration was observed with an increase in number of alternate wetting and drying cycles. Hence, when pavement design factors are considered, in addition to prolonged exposure to wetting condition , the effect of alternate wetting and drying should also be taken into account.

Road transport; pavement; wetting and drying; coir; reinforcement; SMA; rutting;