Compressive Performance of Fiber Reinforced Recycled Aggregate Concrete by Basalt Fiber Reinforced Polymer-Polyvinyl Chloride Composite Jackets

Abstract

The development of recycled aggregate concrete (RAC) provides a new approach to limiting the waste of natural resources. In the present study, the mechanical properties and deformability of RACs were improved by adding basalt fibers (BFs) and using external restraints, such as a fiber-reinforced polymer (FRP) jacket or a PVC pipe. Samples were tested under axial compression. The results showed that RAC (50% replacement of aggregate) containing 0.2% BFs had the best mechanical properties. Using either BFs or PVC reinforcement had a slight effect on the loadbearing capacity and mode of failure. With different levels of BFs, the compressive strengths of the specimens reinforced with 1-layer and 3-layer basalt fiber reinforced polymer (BFRP) increased by 6.7%–10.5% and 16.5%–23.7%, respectively, and the ultimate strains increased by 48.5%–80.7% and 97.1%–141.1%, respectively. The peak stress of the 3-layer BFRP-PVC increased by 42.2%, and the ultimate strain improved by 131.3%, relative to the control. This reinforcement combined the high tensile strength of BFRP, which improved the post-peak behavior, and PVC, which enhanced the structural durability. In addition, to investigate the influence of the various constraints on compressive behavior, the stress-strain response was analyzed. Based on the analysis of experimental results, a peak stress-strain model and an amended ultimate stress-strain model were proposed. The models were verified as well; the result showed that the predictions from calculations are generally consistent with the experimental data (error within 10%). The results of this study provide a theoretical basis and reference for future applications of fiber-reinforced recycled concrete.