Date of Completion
Master of Science in Construction Engineering
Structural and Geotechnical Engineering
Dr. Metin Oguzmert
Annually, tons of plastic wastes end up in landfills and the oceans through indiscriminate dumping, constituting a major source of pollution to the environment and threat to human health and marine lives. It therefore necessitates an innovative strategy to help mitigate the environmental hazards caused by this pollution. A feasible eco-friendly strategy is by using granulated plastics, fibers or regrinds in concreting. This research explored the feasibility of this strategy by testing the compressive and flexural strengths of hardened concrete specimens containing varying percent of plastic aggregates used as partial replacement for fine aggregates. The compressive strength of specimens of 1:3:3 (cement:sand:gravel) concrete mixes containing 10%, 20%, 30% and 40% PET plastic with a constant water-to-cement ratio of 0.55, were tested at 7, 14, and 28 days. The flexural strength was also tested at 28 days. The result shows that the 28 days compressive and flexural strength of concrete can be enhanced by replacing up to 20% of sand with PET regrinds. Compared to the reference case (0% case), the results show that for 10% sand replacement, the 7 and 28 days compressive strength of concrete increased by 5.38% and 3.36% respectively, and the 28 days flexural strength increased by 0.04%. For 20% sand replacement, the 7 and 28 days compressive strength of concrete showed a 4.15% increase and then a 2.10% decrease respectively, and the 28 days flexural strength decreased by 13.11%. Beyond 20% sand replacement, the results showed a continuous decrease in compressive and flexural strength.
Available for download on Saturday, December 23, 2023