Influence of Waste Tire Rubber on Fresh and Hardened Properties of Self-Compacting Rubberized Concrete (SCRC)

Abstract

This study investigates the influence of waste tire rubber on fresh and hardened properties of self-compacting concrete (SCC). Seven different SCC mixtures were designed: The reference mixture was made with natural aggregate and six SCC mixtures made with 5%, 10%, 15%, 20%, 25% and 30% replacement level of total aggregate volume. Natural fine aggregates were replaced by recycled waste tire rubber with maximum grain size of 4 mm. Flowability, viscosity, passing ability and porosity of fresh SCC mixtures were determined by means of slump flow, L-box, J-ring and air content – pressure method. Mechanical properties of hardened SCC were evaluated by means of compressive strength, flexural strength and static modulus of elasticity, while durability was expressed with two SCC hardened state properties, water permeability and gas permeability. The test results reveal that waste tire rubber affects the fresh and hardened SCC properties. With a higher amount of waste tire rubber in concrete mixtures, degradation in SCC fresh and hardened properties was observed. However, the addition of waste tire rubber up to 10% of total aggregate volume shows that it is possible to implement recycled rubber in SCC and to successfully satisfy both fresh and hardened SCC properties.