Properties of concrete containing high-calcium fly ash artificial aggregate

Abstract

The work aims to develop a concrete mixture with cold-bonded fly ash aggregate based on high-calcium fly ash and experimentally study its physical and mechanical properties. The results of experimental studies of concrete with artificial coarse aggregate based on fly ash from Berezovskaya Thermal Power Plant showed compressive strength of 28.92 MPa, flexural strength of 4 MPa, coefficient of linear thermal expansion of 14.5 * 10−6 K−1, modulus of elasticity of 16 *109 Pa, heat of hydration on the 10th day - 340 kJ/kg, shrinkage deformation of −1.8 mm/m. It has been established that heat treatment of fly ash aggregate for 8 hours at a temperature of 80 °C after 7 days of air storage did not positively affect the physical and mechanical properties of concrete. The compressive strength at the age of 28 days and the modulus of elasticity of the specimens with coarse aggregate after heat treatment were lower by 41% than that of the control mixture.