Structural performances of self-curing concrete using recycled coarse aggregate - A comparative study

Proper curing ensures that concrete meets the intended structural and durability requirements. A poorly cured concrete may result in development of early-age cracks due to reduction of internal relative humidity. Self-curing is one of the most effective curing techniques that are used in the modern construction industry. Many studies have shown that buildings are a significant contributor to natural resources depletion and environmental emissions. Demolished concrete from buildings has become a great concern in terms of waste disposal. After applying proper recycling techniques, it can be used as an alternative source for normal coarse aggregate which not only will help resolve waste disposal issues but also provide a solution for the short supply of normal coarse aggregate for concrete. This research makes an attempt to investigate the performance of self-curing concrete with recycled coarse aggregate by evaluating its structural properties in terms of compressive strength, split tensile strength and flexure strength. The comparative results show that recycled coarse aggregate achieves up to 94.82% of the normal aggregate compressive strength with normal curing and 91.73% normal aggregate when self-curing agent is used. A compressive strength increase of 3% was observed between normal curing and self-curing specimens with recycled coarse aggregate. It is also seen that an average structural performance decrease of 13% is recorded for self-curing test specimens when the aggregate is changed from normal to recycle.