Experimental and Theoretical Analysis of Hybrid Polymer Composite Behavior

This research examines the cyclic tensile properties of a hybrid fiber reinforced polymer (FRP) composite made of polypropylene (PP) and glass fibers. The hybrid FRP is intended to take advantage of the high strength and stiffness of glass fibers and the improved ductility of PP fibers to enhance the seismic performance and repairability of structural materials under cyclic loading conditions. Cyclic tensile tests were performed to assess the stress-strain behavior, including envelope curves, unloading modulus, and plastic strain accumulation. The effect of the volume fraction of glass fiber on the behavior of the composite was also investigated. The results indicate that hybrid FRP has a lower plastic strain than pure PP FRP, providing better seismic repairability. In addition, the hybrid FRP's stress-strain performance exhibited a close-to-linear behavior prior to peak loading, which was followed by a sudden decrease in stress. The research sheds important light on the development of hybrid FRP materials for use in structural reinforcement, especially earthquake-resistant structures, for enhancing repairability and durability.