Influence of rubber particles on the properties of foam concrete

This paper addresses the fresh and hardened properties of foam concrete incorporating crumb rubber from car tyre waste as partial replacement of concrete sand by volume. Different parameters including water/cement ratio, rubber content, and concrete density were investigated. Some fresh concrete properties such as density, flowability and consistency have been investigated. Different hardened concrete properties were investigated including compressive strength, tensile and flexural strengths, modulus of elasticity, damping ratio, impact resistance, and water absorption. Investigations into the effect of elevated temperature on the concrete strength was also carried out. The results of this study showed that foam rubberized concrete with compressive strength above 10 MPa and density below 1600 kg/m(3) could be achieved by using 17% rubber content of total concrete volume, although a reduction in concrete compressive strength was observed. However, there was an increase in concrete splitting tensile and flexural strengths for mixes with rubber content up to 8.5% and 17% of total concrete volume, respectively. The elevated temperature showed a reduction on compressive strength of 3.3%, 14.8%, 29.4%, and 40.4% for mixes with 0%, 8.47%, 17%, and 47.8% total rubber content, respectively. The impact resistance and damping ratio also increased with increasing rubber content. The damping ratio increased by 21.1% and 17.3% for the mixes with 17% and 47.8% total rubber content, respectively, compared with that of the control mix without rubber.