INFLUENCE OF INITIAL CaO/SiO₂RATIO ON THE HYDRATION OF RICE HUSK ASH-Ca(OH)₂AND SUGAR CANE BAGASSE ASH-Ca(OH)₂PASTES

Effects of slag content on the residual mechanical properties of ambient air-cured geopolymers exposed to elevated temperatures

“…In the case of geopolymers containing slag, however, new crystalline peaks of "calcite" and "calcium silicate hydrate (CSH)" are noticed at the 2θ angles of 29.4°and 50.17°, and the height of the calcite/CSH peaks also increases with increases in slag contents indicating the formation of more calcium-based reaction products in the C-(N)-A-S-H gels, which also correlates well with the denser microstructure observed in the geopolymers containing 30% slag than in the other geopolymers observed in the above SEM analysis. It has been reported by numerous studies that semi-crystalline CSH and calcite peaks overlap at 2-theta angles of 29.45°and 50.17° [23][24].…”

“…At 800°C, however, cracks appeared in all ambient air-cured geopolymers and the cracks width and depth increased with increases in slag contents. In heat-cured fly ash geopolymers, on the other hand, the intensity of cracking at 800°C is much less than in ambient air-cured geopolymers containing high slag contents [24]. It has been shown in next section that the compressive strengths of ambient air-cured geopolymers containing high slag contents (e.g.…”

Machine Learning‐Based Modeling with Optimization Algorithm for Predicting Mechanical Properties of Sustainable Concrete

“…e flexural strength at higher replacement level (20%, 30%, and 40% SCBA) reduced by 15.5%, 28.8%, and 42.5%, respectively. According to available literature, the increased tensile and flexural strength at 10% SCBA may be due to the microfibrous nature of SCBA, which is related with CSH formation, and also due to the formation of aluminates, resulting in needle-like structure [80,81]. e interlocking of these needles takes place between hydrated paste and may directly enhance the tensile and flexural strength.…”

Production of agroindustrial ashes with pozzolanic activity via acid leaching, conjugated burning and ultrafine grinding

“…Studies on pozzolans have shown improvements in cementitious properties regarding rheological behavior (CORDEIRO; TOLEDO FILHO; FAIRBAIRN, 2008), durability (MALHOTRA;MEHTA, 1996;FAIRBAIRN, 2008;HOPPE FILHO et al, 2014) and mechanical performance (MALHOTRA;MEHTA, 1996;FAIRBAIRN, 2008;CORDEIRO et al, 2018). This is due to the increased formation of hydrates because of pozzolanic reactions (MALHOTRA;MEHTA, 1996;SOUZA et al, 2014) and the filler effect on cement pastes provided by the fine or ultrafine particles of mineral addition (LAWRENCE; CYR; RINGOT, 2003;CORDEIRO et al, 2008).…”