Thesis (MSc) - Cyprus International University Institute of Graduate Studies and Research Engineering Management Department

Includes References (sheets 110-136)

ABSTRACT
The escalating consumption of plastics and the surge in Pfa generation have raised significant environmental concerns, prompting the urgent need for innovative waste
management strategies. This study investigates the feasibility and effectiveness of
incorporating PW and Pfa as replacements in concrete production. Emphasizing the
environmental hazards posed by PW and Pfa accumulation, the study explores their
potential benefits when integrated into construction materials. Key objectives of this
study include evaluating the impact of PW and Pfa on concrete properties and
performance, encompassing factors like fire resistance, acid attack resistance, water
absorption, toughness, and workability strength. Environmental considerations are
paramount, with assessments focused on waste reduction, reductions in carbon dioxide
emissions, and pollution prevention. To comprehensively assess the viability of this
approach, different replacement percentages (5%, 15%, and 25%) of Pfa and PW in
concrete mixes are analyzed. Cost-effectiveness is scrutinized through a comparative
analysis against traditional concrete materials. This study suggests employing PW
pellets in concrete as a fine aggregate replacement since they are less expensive and
emit less CO2, as well as Pfa as a replacement for cement, which can reduce
greenhouse gas emissions, electricity costs, and solid waste volume. The effects of
replacing fine aggregate with PWP and cement with Pfa on fire resistance, density,
workability, acid attack, and water absorption. Mechanical qualities including
compressive strength, flexural, and splitting tensile strength were also investigated,
and the findings provide insight into the potential use of PW and Pfa as replacements
in concrete manufacturing. The results demonstrated that increasing the cement
substitution with Pfa improved the properties of the concrete. The 25% Pfa substitution
produced the best outcomes. Fine aggregate replacement with PWP at 5% improved
the characteristics, however, the combined replacement at 5% Pfa and 5% PWP
performed better. When 25% Pfa is blended with 5% PWP, compressive, flexural, and
splitting tensile strength all increased. Mixed percentage concrete improves the
mechanical and durability attributes of standard concrete while also ensuring
environmental benefits.
Keywords: Cement Replacement, Compressive Strength, Fine Aggregate Replacement, Flexural Strength, Fly Ash, Plastic Waste, Splitting Tensile Strength, Sustainability.