EXPERIMENTAL INVESTIGATIONS OF COIR FIBRE AND CRUMB RUBBER MODIFIED BITUMINOUS MIXES

Abstract

A country’s road network is essential to its economic growth, social integration and trade. Inadequate transportation facilities may have an impact on a country’s socio-economic and cultural development. Increased traffic volume and severe loading conditions in India necessitate massive construction of better, more durable and more effective roads that avoid or reduce bituminous asphalt distress. As a result, in order to increase the performance of flexible pavements, these issues must be addressed. One method for improving pavement performance is to modify the asphalt mixes. Coir fibres of size 6 mm and crumb rubber of size 0.8 mm is used for modification in this study. Marshall stability test was done on the mixes to evaluate the stability and flow values. Volumetric properties of the mixes were also evaluated. Coir fibre and crumb rubber modified mixes shown higher stability values than normal mixes. Target air voids is achieved at 8% coir fibre and 6% crumb rubber content. To understand the moisture susceptibility of the mixes indirect tensile strength was conducted. Tensile Strength Ratio (TSR) of the modified mixes were also higher than normal mixes. It indicates modified mixes were less susceptible to moisture damage. Rut depth of the mixes were also evaluated using Wheel rut testing machine. Modified mixes shown lower rut depth values than normal mixes.