Mixture Optimization of Green Reactive Powder Concrete with Recycled Powder

Abstract

Recycled powder (RP), generated from construction waste, can be used as supplementary cementitious material. It is promising to use recycled powder in reactive powder concrete (RPC) to develop a green high-performance mixture with reduced cost. Based on previous study, different mixtures were designed and a comprehensive experimental program was developed to investigate the optimization of green reactive powder concrete (GRPC) mixture proportions systematically. Influences of superplasticizer amount, fine aggregate type, water:cementitious materials ratio (W:CM), recycled powder amount, silica fume amount, and steel fiber amount on the flowability, compressive strength, and flexural strength of GRPC were investigated. Considering the properties, cost, and environmental savings, superplasticizer ratio of 1.0%, recycled powder replacement of 30%, silica fume amount of 15%, steel fiber proportion of 2.0%, and W:CM of 0.16 are suggested, and natural sand is suggested to replace crushed quartz.