Research on Mechanical and High Temperature Resistance Properties of Recycled Aggregate Concrete Containing Mineral Admixtures

To study the influence of mineral admixtures on the basic characteristics and high temperature resistance of recycled aggregate concrete, fly ash, iron slag and rice husk ash were used to modify recycled aggregate concrete. High temperature and mechanical tests were carried out. The results show that with the increase of temperature, the density and ultrasonic velocity of the sample continue to decrease; the density and ultrasonic velocity of the sample prepared by the additive method are greater than that of the sample prepared by the alternative method; the compressive strength and relative elastic modulus increase first and then decreases with the increase of the mineral，reaching the maximum at 5%~10%. As the temperature increases, the compressive strength first increases and then decreases, reaching the maximum at 100°C; and when the mineral admixture is added by the additive method, the strength and elastic modulus of the sample are higher. Enhancement of high temperature resistance of recycled aggregate