Flexural and Shear Strengths of Structural Concrete Containing Plastic Wastes and Styrene–Butadiene Rubber Latex

Abstract

The cross-linked polyethylene (XPE) plastic wastes are not recyclable, requiring appropriate disposal alternatives. This paper assesses different solutions that could compensate the inevitable curtail in the structural performance of reinforced concrete (RC) beams produced using XPE-modified concrete mixtures. The XPE wastes were derived from damaged high-voltage electrical insulators, which were shredded into small pieces and incorporated during concrete batching at 1.5–4.5%, by volume. At relatively high XPE rate of 4.5%, test results showed that the residual flexural and shear strengths of RC beams were approximately 72% of ultimate capacity, given the poor XPE/cement matrix bonding as well as inferior concrete strength, density, and aggregate interlock mechanism. The reduction in water-to-cement ratio from 0.44 to 0.35 partially reinstated the beam’s strength to 82% of ultimate capacity. The conjuncture use of 7.5% styrene–butadiene rubber latex and 1% steel fibers was efficient to strengthen the XPE-modified concrete skeleton, which restored the ultimate flexural and shear capacities to 93% and 97%, respectively.