Sustainability, Eco-Point and Engineering Performance of Different Workability OPC Fly-Ash Mortar Mixes.

Area of Science:

• Materials Science
• Environmental Engineering
• Civil Engineering

Background:

• Portland cement production is a major source of CO₂ emissions.
• Industrial waste materials like fly ash offer a sustainable alternative.
• Reducing the environmental footprint of construction materials is crucial.

Purpose of the Study:

• To evaluate the engineering performance of mortar with varying fly ash replacement percentages.
• To assess the CO₂ footprint and environmental benefits of using fly ash in mortar.
• To determine the optimal fly ash content for self-compacting mortar (SCM).

Main Methods:

• Mortar mixes were prepared with 10%, 20%, 40%, and 60% fly ash replacing Portland cement.
• Different water/binder ratios and superplasticizer dosages were used to achieve normal, high, and self-compacting workability.
• Compressive strength was measured to assess engineering performance.
• CO₂ footprint was calculated for each production stage.

Main Results:

• The optimum mix design was achieved at a 10% fly ash replacement rate.
• Total production emissions were reduced by up to 56% with a 60% fly ash replacement.
• Eco-points were reduced by 80% at maximum fly ash utilization.
• Fly ash incorporation reduced sulfur leaching by 5%–27% and landfill area by 15%–91%.

Conclusions:

• Replacing Portland cement with fly ash in mortar is an effective strategy for reducing CO₂ emissions and environmental impact.
• Fly ash utilization in mortar enhances sustainability by decreasing waste and potential soil toxicity.
• The study demonstrates the viability of using industrial waste for improved mortar performance and reduced ecological burden.