Long-Term Mechanical And Durability Properties Of High-Performance Recycled Aggregate Concrete

Abstract

This paper presents the findings of longterm properties of high-performance recycled aggregate concrete (HPRAC) utilizing recycled aggregates (RA) derived from Taiwan. '1 he RA was cleaned and the properties of RA were investigated. The mix proportion of concrete using Densified mixture design algorithm (DMDA) to design the ingredients of the HPRAC. The HPRAC samples are used with a water-to-binder ratio of 0.35, and either natural aggregate (NA) or recycled aggregate (RA) combined together. The effect of replacing 0%, 30%, and 100% natural coarse aggregate (NCA) by recycled coarse aggregate (RCA) in two group mixture, which are natural fine aggregate group and recycled fine aggregate group is investigated. Both fresh and hardened properties of the HPRAC are studied. It was found that, after 150 days, the compressive strength index of the HPRAC range from 31.7 to 60,1 MPa. In addition, all of the HPRAC specimens in this study show the excellent durability performance with electrical surface resistivity is above 20 kfl.crn, the chloride ion penetration resistivity ranges between very low and moderate risk of corrosion, ultrasonic pulse velocily values is higher than 3660 m/s.