Compressive Stress–Strain Relationship of Concrete Containing Coarse Recycled Concrete Aggregate at Elevated Temperatures

Abstract

This study investigated the compressive stress-strain curves of concrete produced with coarse recycled concrete aggregate (RCA) at temperatures in the range of 20°C to 800°C. Three concrete series were produced with coarse RCA replacement levels of 0%, 50%, and 100%. The compressive properties of coarse RCA concrete at elevated temperatures, including compressive strength, modulus of elasticity, peak strain, and complete stress-strain curve, were obtained from the experiment. The experimental results show that both compressive strength and modulus of elasticity diminished with increasing temperature, whereas peak strain increased correspondingly. The effects of coarse RCA replacement level on the relative compressive properties of coarse RCA concrete were indefinite. Based on the experimental results, a model was proposed to generate the compressive stress-strain relationships for coarse RCA concrete in the 20°C to 800°C range.