Investigation of the Effects of Polymer on the Compressive Strength of Fiber-Reinforced Concrete

In this study, the combined effects of polypropylene (PP) fibers and acrylic resin as a polymeric admixture on the compressive strength of concrete were investigated. The objective was to optimize the mechanical performance of concrete through the appropriate selection of these two components, and to examine the influence of the water-to-cement (w/c) ratio as a key parameter affecting concrete behavior. Standard cubic specimens were prepared with three w/c ratios (۰.۴, ۰.۵, and ۰.۵۵), various PP fiber contents (ranging from ۰.۲% to ۱.۲%), and different percentages of acrylic resin (۳%, ۵%, and ۷%). The compressive strength of the specimens was evaluated at ۷, ۱۴, and ۲۸ days. The results demonstrated that reducing the w/c ratio enhanced compressive strength but negatively affected the workability of the concrete mix. A w/c ratio of ۰.۵ was identified as the optimal value, offering a balance between strength and workability. Moreover, the addition of ۰.۴% PP fibers significantly improved the ۲۸-day compressive strength. The combination of ۰.۴% PP fibers with ۳% acrylic resin yielded the greatest improvement, resulting in a ۲۶.۶% increase in compressive strength compared to the control specimens. This enhancement is attributed to the synergistic effect between fiber reinforcement and the improved matrix bonding provided by the polymeric admixture. Overall, the findings suggest that the combined use of PP fibers and acrylic resin, at optimized dosages, provides an effective strategy for enhancing the compressive strength and performance of concrete, with promising implications for structural applications.

Keywords:

Concrete , polypropylene fibers , acrylic resin , compressive strength , water-to-cement ratio , polymeric admixture