Properties of High-Performance Self-Compacting Rubberized Concrete Exposed to High Temperatures

Abstract

Self-compacting concrete (SCC) is a unique type of concrete material where vibration or compaction is avoided by including super plasticizer in the fresh mixture to achieve homogenous compaction. SCC offers improved deformability, filling rate, high segregation resistance, and reduced blocking in congested reinforced areas where vibration is not possible. When rubber aggregates from waste tires are incorporated into SCC, it a new mixture is created, self-compacting rubberized concrete (SCRC), which resists environmental destruction and is more economically valuable. In this study, 2–5-mm and 5–10-mm crumb rubber (CR) aggregates replaced natural aggregates in SCC at volume ratios of 10%, 20%, 30%, and 40%. The 2–5-mm CR aggregates replaced fine aggregate, and the 5–10-mm CR aggregates replaced coarse aggregate. This study focused on the impact of elevated temperatures on SCRC through its residual properties: compressive and tensile strength, modulus of elasticity, mass loss, and spalling intensity. The residual properties were measured by heating 100×200-mm cylindrical specimens to 100°C, 300°C, and 600°C. The results indicated that CR as an aggregate enhanced deformation and energy absorption but decreased workability and mechanical properties. Also, test results showed that SCRC mixes with 2–5-mm CR aggregates had less spalling than those with 5–10-mm aggregates, whereas massive spalling occurred in both CR size ranges with 40% replacement rates at 600°C heat.