Resilient Modulus Studies on Fly Ash and Granulated Rubber Composites

In the fast-growing world, solid waste management is one of the key aspects to be considered for a sustainable environment. In the present study, two solid wastes, namely, fly ash and rubber wastes are considered and studied to evaluate the feasibility of utilizing this waste composite as a subgrade material in the pavement system. Resilient modulus of the material is one of the essential design parameters to design pavements over such fill material. Two percentages of granulated rubber of nominal size equal to 9.5 mm is added to fly ash and the resilient modulus of the composite material is determined from cyclic triaxial tests. The effect of curing period and water content is also investigated by resilient modulus testing on samples prepared at optimum moisture content (OMC%) and OMC ± 2% (wet and dry side of optimum) and cured for two periods, viz. 6 h and 24 h. The resilient modulus is found to increase with the curing period with the highest values recorded for samples prepared at OMC. The resilient modulus for fly ash-granulated rubber composite at OMC after 24 h of curing period ranges between 37 and 114 MPa.