Report
Alkaline activation of fly ash and coal mining tailings to produce pervious paving blocks with seashells as aggregates
— 2024
Key information
Authors:
Published in
January 2024
Description
This comprehensive study explores the viability of a novel blend of fly ash and coal mining tailings as precursors for alkali-activated concrete, focusing on pervious concrete pavement block production. In this investigation, sand is replaced with seashell sand and the impact of CO2 curing at various intervals is assessed. Despite a reduction in compressive and splitting tensile strength, the ash/tailings blend proves to be a promising, sustainable alternative for waste utilisation and landfill reduction. Carbonation curing significantly enhances both the compressive and splitting tensile strengths, with optimal performance observed in the 50% ash/50% tailings mix. The study delves into the implications of the novel precursor on the properties of the blocks, including slip resistance, abrasion resistance, density, porosity, and water stability. Notably, the blocks exhibit excellent slip resistance even after prolonged CO2 exposure during carbonation curing. Abrasion resistance is significant, with reduced mass loss as curing time increases. Carbonation induces considerable microstructural densification, enhancing density. A consistent trend shows decreased accessible porosity and reduced water absorption with prolonged carbonation. Importantly, water stability improves with reduced permeability. These findings suggest potential applications for the ash/tailings blend in environmental-friendly construction materials, emphasising the need for further research and optimisation in this emerging field.
Publication details
Authors in the community:
Ghandy Lamaa
ist1101180
Rui Vasco Pacheco Santos da Silva
ist156561
Publication language (ISO code)
eng - English
Rights type:
Only metadata available
Financing entity
PROJECTO FCT EXPL/ECI-EGC/0288/2021