A study on the potential use of paper sludge ash in concrete with glass aggregate

This short communication focuses on the potential use of paper sludge ash, a waste product of the paper making industry, as an innovative binder partially replacing cement in concrete with glass aggregate. After preliminary testing using binary or ternary CEM-II mixes with paper sludge ash/pulverised fly ash, a suitable mix for concrete with glass aggregate was identified. Concrete mixes with partial or full natural sand replacement by waste glass aggregate were then produced and showed appropriate strengths and overall similar or better water absorption characteristics than control mixes with natural aggregates, without manifest alkali-silica reaction problems. This shows potential for applications in precast dry mix concrete units based on the required strengths that were achieved.