Mechanical Properties of Polypropylene Fiber Recycled Brick Aggregate Concrete and Its Influencing Factors by Gray Correlation Analysis

Making construction waste into raw materials for recycled concrete is beneficial resource conservation and environmental protection. This paper investigated the effects of different brick aggregate (RBA) replacement rates (30%, 50%, 70%, 100%) contents polypropylene fibers (PPFs) (0.08%, 0.10%, 0.12%, 0.16%, 0.2%) on mechanical properties concrete. Gray correlation was also used to analyze degree effect factors The results showed that decreased when natural coarse (NCA) replaced with RBA, while PPFs could better improve RBA improvement compressive flexural optimal PPF content 0.12%; tensile 0.2%. In addition, significantly improved toughness gray degrees between strength (tensile strength, strength) NCA, were 0.8964 (0.8691, 0.8935), 0.7301 (0.6530, 0.7074), 0.5873 (0.5870, 0.5840), respectively.