Our present study aims to investigate the optimal use of waste tire rubber as a fine
aggregate in concrete and their sensitivity to high temperature effect. Five different
concrete compositions were prepared: a reference concrete (RC) made with natural
fine aggregate (sand) and coarse aggregate (dolomite) and four concrete mixes with
replacement rates of 4%, 8%, 12% and 16% of sand by crumb rubber from waste
tires. For the effect of elevated temperature: Similar specimens were exposed to a
period of 4 hours to temperature of 70°C, to study the effect of high daily
temperature, and a period of 2 hours for both temperatures 200° C and 400° C to
study the effect of fire. After cooling down to ambient temperature, the
compressive strength, flexural strength and the splitting tensile strength were
measured and compared with the values that obtained before fire exposure. The inhand
study indicates a gradual decrease in compressive, splitting and flexural
strengths of concrete for partial substitution of crumb rubber aggregate in concrete.
In addition, more decrease in these strength values are resulted after exposing the
similar specimens to high temperature. While the inclusion of rubber particles
reduces the rate of compressive strength loss at high temperature.