Sustainable fly ash‐based geopolymer composites: The influence of RAP aggregates and silica fume on strength, durability, and microstructural properties

Structural Concrete, Journal Year: 2025, Volume and Issue: unknown

Published: March 20, 2025

Abstract This study investigates the effects of reclaimed asphalt pavement (RAP) aggregates and silica fume (SF) on mechanical, durability, microstructural properties fly ash (FA)‐based geopolymer composites (GC) under varying curing conditions. GCs were prepared with RAP contents 0%, 15%, 30%, 60% as replacements for river aggregate (RA) partial replacement FA by 15% SF. Samples cured at 60°C 90°C, their performance was evaluated through compressive flexural strength tests, freeze–thaw (F‐T) resistance, high‐temperature exposure, sorptivity, porosity, analysis. The results reveal that substituting RA demonstrated optimal content enhancing strength, increases 33.64% 8.04% 90°C. At 30% RAP, improvements smaller (7.36% 7.37% 90°C), while led to reductions 0.97% 8.12% respectively. mixture containing 100% a best performance, exhibiting lowest loss 750°C. after 50 F‐T cycles observed in 90°C FA. Mixtures exhibited cycles, demonstrating enhanced durability. superior incorporation compared reference without irrespective temperature. highest resistance elevated temperatures, minimal However, increasing greater deterioration due thermal degradation bitumen‐coated aggregates. Replacing SF significantly reduced causing over 90%

Language: Английский

Durability performance of one-part alkali-activated self-compacting concrete mixes under aggressive and elevated temperature conditions

Sustainable Chemistry and Pharmacy, Journal Year: 2025, Volume and Issue: 45, P. 102025 - 102025

Published: April 29, 2025

Language: Английский