Fresh properties and compressive strength of high calcium alkali activated fly ash mortar

被引：40
作者：
Gomaa E. [1 ]
Sargon S. [1 ]
Kashosi C. [1 ]
ElGawady M. [1 ]
机构：
[1] Department of Civil, Architectural and Environmental Engineering, College of Engineering and Computing, Missouri University of Science and Technology, Rolla
来源：
Journal of King Saud University - Engineering Sciences | 2017年 / 29卷 / 04期
关键词：
42;
D O I：
10.1016/j.jksues.2017.06.001
中图分类号：
学科分类号：
摘要：
This paper reports the fresh properties and compressive strength of high calcium alkali-activated fly ash (AAFA) mortar. Two different sources of class C fly ash, with different chemical compositions were used to prepare alkali-activated mortar mixtures. Four different sodium silicate to sodium hydroxide (SS/SH) ratios of 0.5, 1.0, 1.5, and 2.5 were used as alkaline activators with a constant sodium hydroxide concentration of 10 M. Two curing regimes were also applied, oven curing at 70 °C for 24 h, and ambient curing at 23 ± 2 °C. The rest time, i.e., the time between casting the mortar cubes and starting the oven curing was 2 h. The results revealed that the setting time, and workability of mortar decreased with increasing the alkali to fly ash ratio, and decreasing the water to fly ash ratio. The optimum sodium silicate to sodium hydroxide ratio was 1.0, which showed the highest compressive strength and setting time. An increase of sodium silicate to sodium hydroxide ratio to 2.5 led to a significant reduction in the setting time, and workability of mortar. The 7-day compressive strength of the mortar approached 20.80 MPa for ambient cured regime and 41.10 for oven cured regime. © 2017 King Saud University
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页码：356 / 364
页数：8
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