Experimental study on flexural capacity of PVA fiber-reinforced recycled concrete slabs

The flexural tests were conducted on 21 polyvinyl alcohol (PVA) fiber-reinforced recycled concrete slabs to investigate the influences of the reinforcement ratio, the PVA fiber content, the replacement ratio of recycled coarse aggregate (RCA) and the span-thickness ratio on the mechanical behaviors. The failure mode of the PVA fiber-reinforced recycled concrete slabs was the yielding of the longitudinal tensile reinforcement, slight crushing of concrete in the compression zone, and pulling out or breaking of PVA fiber at cracking position. The ultimate moment, cracking moment, moment corresponding to 0.2 mm-crack width and yield moment decreased as the replacement ratio of RCA or the span-thickness ratio increased while they increased as the reinforcement ratio or the PVA fiber content increased. Considering the impact of the PVA fiber content and the replacement ratio of RCA, the calculation formulas for conveniently predicting the flexural capacities of the PVA fiber-reinforced recycled concrete slabs were proposed. The formula prediction results were in good agreement with the test data.