TY - JOUR AU - Kovalchuk, G. AU - Fernández-Jiménez, A. AU - Palomo, A. PY - 2008/09/30 Y2 - 2024/03/28 TI - Alkali-activated fly ash. Relationship between mechanical strength gains and initial ash chemistry JF - Materiales de Construcción JA - Mater. constr. VL - 58 IS - 291 SE - Research Articles DO - 10.3989/mc.2008.v58.i291.101 UR - https://materconstrucc.revistas.csic.es/index.php/materconstrucc/article/view/101 SP - 35-52 AB - Alkali-activated fly ash is the primary component of a new generation of high-strength, durable binders with excellent mechanical properties and durability (on occasion bettering traditional Portland cement performance). Moreover, development of these cements may contribute to mitigating CO<sub>2</sub> emissions, since the base material is an industrial by-product. The present study was conducted to determine the effect of the composition of the initial materials (SiO<sub>2</sub>/Al<sub>2</sub>O<sub>3</sub> and Na<sub>2</sub>O/Al<sub>2</sub>O<sub>3</sub> ratios) on the mechanical properties, nature and composition of the reaction products. The results obtained indicate that there is no linear relationship between these ratios and mechanical strength, but rather a series of optimal values above and below which strength declines. In the specific case of the ratios studied in the present paper, these values were: SiO<sub>2</sub>/Al<sub>2</sub>O<sub>3</sub>= 4.0 and Na<sub>2</sub>O/Al<sub>2</sub>O<sub>3</sub>= 1.0 (molar ratios). ER -