To evaluate the feasibility of using recycled micro powder of construction waste as an admixture in C30,C35,C40 recycled concrete,recycled micro powder obtained from dust collection in construction waste disposal plant was selected to replace fly ash in differ-ent proportions to prepare C30,C35,C40 recycled concrete,and the variation laws of its water reducer dosage,compressive strength,flex-ural strength,dynamic elastic modulus,electric flux and other indicators were investigated.The results show that adding recycled micro powder slightly increases the dosage of water reducing agent and has a certain deterioration effect on the compressive strength,dynamic e-lastic modulus,flexural strength,and chloride ion permeability of recycled concrete.However,when the replacement rate of recycled micro powder does not exceed 25%,the deterioration effect on compressive strength and flexural strength can be controlled within 5%.In addi-tion,replacing fly ash with recycled micro powder can reduce the comprehensive cost of concrete materials,have significant social and e-conomic benefits.It is feasible to use recycled micro powder as an admixture to prepare C30,C35,C40 recycled concrete.
关键词
再生微粉/再生混凝土/减水剂用量/力学性能/抗氯离子渗透性能
Key words
recycled micro powder/recycled concrete/water reducing agent dosage/mechanical properties/resistance to chloride ion penetration