Mechanical, durability and microstructural characterization of various types of outflows in the production of glass fiber-reinforced sustainable concrete

This experimental program strives to explore the mechanical, durability, and microstructural characterization of glass fiber-reinforced geopolymeric recycled aggregate concrete (GRAC) developed by using five discrete types of outflows. The freshwater was fully swapped with each type of outflow for the GRAC fabrication to assess its influence on the efficacy of GRAC at different testing ages. The microstructural characterization and the mineralogy of fabricated mixes were determined by scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis. The results depict that considering textile factory outflow in the development of GRAC offers the highest strength in tension and compression, which were 19% and 16% improved than that of the GRAC fabricated using fresh water. The application of fertilizer factory outflow in the manufacturing of GRAC presented the highest mass loss due to an attack of H₂SO₄ solution and the highest chloride attack penetration. The SEM and XRD results indicated that in GRAC made with fertilizer factory and domestic sewage effluents, the lower portlandite, dolomite, and labradorite intensities encourage the formation of calcium phosphate and CaZn₂(OH)6H₂O, which lowers the geopolymerization and strength of concrete mixes. The mixes with textile and service station outflow included much more hatrurite implying that these mixes contained more C−S−H hydrate. Consequently, the mix produced using textile factory effluent outperformed in terms of mechanical and durability performance. The addition of fly ash to all concrete mixes produced the maximum quantities of silica and labradorites so that the fly ash and Ca(OH)₂ the pozzolanic reaction might produce more C−S−H gel and densify the internal structure.