The evaluation of self consolidating concrete incorporating crushed concrete waste aggregate

Self consolidating concrete (SCC) is an innovative concrete that does not require vibration for placing and compaction. It offers a rapid rate of concrete placement, with faster construction times and ease of flow around congested reinforcement. The improved construction practice and performance, combined with the health and safety benefits, make SCC a very attractive solution for both precast concrete and civil engineering construction. If the production of concrete wastes is not managed properly, Malaysia will face major environmental problems. The Government will have to bear the unnecessary costs for clean-ups, repairs and protection measures on illegal dumping areas and providing more landfills. Recycling of waste concrete as crushed concrete waste aggregate (CCWA) for new concrete is beneficial for environmental preservation and effective utilization of resources. This study is to determine the compressive strength performance of SCC using CCWA as coarse aggregate with various replacement percentages of 0%, 25%, 50%, 75% and 100% of CCWA to normal aggregate for grade 30 N/mm² concrete. The specimens were tested for compressive strength at 3, 7, 14 and 28 days age. Results indicated that the compressive strength of SCC containing up to 25% CCWA coarse aggregate replacement is comparable to the compressive strength of normal aggregate SCC.