Research on The Effect of Recycled Aggregate Replacement Rate on The Performance of Fresh Concrete

Abstract In order to improve the utilization rate of recycled aggregate from construction waste, this paper studies the influence of recycled aggregate replacement rate on the performance of fresh concrete. The slump, 7d and 28d unconfined compressive strength of fresh concrete were studied by mixing recycled concrete with different replacement rates. The test results show that: compared with ordinary concrete, when recycled aggregate is completely replaced, the slump of concrete decreases by 58.8%, and the workability becomes worse; in the process of replacement rate from 0 to 100%, the 7d compressive strength decreases slowly, and the decline rate is 16.2%. The 28-day compressive strength decreased by 12.1%, and the mechanical properties decreased.