Influence of Alkaline Electrolyzed Water with Different pH Values on Workability and Strength of Mortar

Abstract

Abstract: Alkaline electrolyzed water has the advantages of strong alkalinity, high activity, ionicity and adsorption. In this study, alkaline electrolyzed water with different pH values (9.5, 10.5, 11.5) was used to prepare fly ash mortar, under the conditions of 0%, 15% and 30% (mass fraction) replacement rate of fly ash, the influence of alkaline electrolyzed water with different pH values on the workability, mechanical properties and the Ca(OH)₂ content of cement hydration products of fly ash mortar was systematically studied. And the structure composition and micro morphology of fly ash paste with different pH values were compared and analyzed by XRD, SEM and other microscopic tests. The test results show that compared with fly ash mortar with ordinary tap water, with the increase of pH value, the fluidity, compressive strength and flexural strength of alkaline electrolyzed water fly ash mortar gradually increase, and the content of hydration product Ca(OH)₂ gradually reduces. When the pH value of alkaline electrolyzed water is 10.5 and the fly ash replacement rate is 15%, the improvement effects of the early strength and fluidity of alkaline electrolyzed water fly ash mortar reach the best, and compared with ordinary tap water mortar, the compressive strength and flexural strength at 28 d increase by 8.4% and 12.5%, respectively. At the same time, compared with ordinary tap water fly ash-cement paste, the clustering and granulation of alkaline electrolyzed water fly ash-cement paste with different pH values are more obvious, which can play a positive role to promote the cement hydration process, improve the fluidity of the mortar, and stimulate the early activity of fly ash. In addition to generating more hydration products such as C-S-H gel and Ca(OH)₂,other hydration products such as potassium feldspar are also generated.

Key words: alkaline electrolyzed water, fly ash mortar, mechanical property, pH value, hydration product

CLC Number:

TU525

XIE Zixi, LIU Guibin, ZHANG Tianyu, LI Qiuyi, WANG Liang. Influence of Alkaline Electrolyzed Water with Different pH Values on Workability and Strength of Mortar[J]. BULLETIN OF THE CHINESE CERAMIC SOCIETY, 2021, 40(11): 3702-3711.

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