Feasibility of crumb rubber as fine aggregate in concrete

Abstract

Production of tires in Indonesia increase steadily, however, utilization of waste tires is very limited. Thus, it is necessary to look for an alternative using waste tires for concrete construction. The objectives focus on using crumb rubber as a waste tire with variations in substitution of crumb rubber to fine aggregate in the concrete of 0%, 10%, 20%, and 30%. In addition, to improve crumb rubber bonding to the concrete mixture, 10% NaOH solution was used. This research is true experimental by making a concrete mixture with a target strength of 20 MPa. The compressive strength testing was conducted at 3, 14, and 28 days, while for splitting test and modulus of elasticity at 28 days. The result showed that each addition 10% of crumb rubber, the weight of concrete volume decreased by 3 %. Compressive strength and splitting strength also decreased with increasing crumb rubber volume. Every 20% addition of crumb rubber, the compressive strength decreased of 26%, while the splitting strength decreased by 10%. The substitution of crumb rubber more than 20% of the volume of fine aggregate is not recommended.