Improvement of the performance characteristics, fire resistance, anti-bacterial activity, and aggressive attack of polymer‐impregnated fired clay bricks-fly ash-composite cements

Abstract

The research addressed the creation of various composite cement mixes by replacing 40 % of OPC with industrial solid wastes, Fly ash (FA), and/or Fired clay bricks (FCB) at different water/powder (w/p) ratios. The composite cement pastes were subjected to polymer-impregnation process, using methyl-methacrylate (MMA) monomer and benzoyl peroxide as an initiator. The physico-mechanical and chemical characteristics of the polymer-impregnated specimens, such as compressive strength, bulk density, total porosity, and polymer load, were examined. The findings showed that, as compared to neat pastes (PF1, PF2, and PF3), the compressive strength (CS) of mixes (PFH1, PFH2, and PFH3) rose considerably after 3 months of hydration by 10.53 %, 12.82 %, and 28.85 %, respectively. Additionally, mix PFH1 with a water/powder (w/p) ratio of 0.35 exhibited the greatest bulk density value (2.215 g/cm3) and the lowest total porosity percentage (12.72 %). Data demonstrated that polymer-impregnation is efficacious to strengthen constructions subjected to high temperatures and aggressive salt attacks. The study additionally revealed that, when thermally treated at 200, 400, and 600 °C, respectively, the CS of PFH1 paste increased by 1.44 %, 1.78 %, and 1.48 % after 14 days of curing, but increased by 10.85 %, 5.20 %, and 7.89 % at curing time of 28 days. Likewise, when CS was compared to that before to polymer-impregnation up to three months, it grew by 48.53 % following immersion in 5%-MgSO4 solutions but increased by 13.49 % after immersion in 5%-MgCl2 solutions.Moreover, the composite with a water/powder ratio of 0.45 demonstrated remarkable anti-bacterial activity against both Gram-negative and Gram-positive bacteria. In conclusion, the study shows that the compressive strength, antibacterial activity, fire resistance, and resistance to aggressive attacks of the composites are all improved by MMA polymer impregnation.