Open Access

ARTICLE

Effect of CSH Crystal Nucleus on Steam-Free Cured Fly Ash Precast Concrete Components

by Ruyi Luo, Yanyan Hu^*, Tingshu He^*, Xiaodong Ma, Yongdong Xu

College of Materials Science and Engineering, Xi’an University of Architecture & Technology, Xi’an, 710055, China

* Corresponding Authors: Yanyan Hu. Email: ; Tingshu He. Email:

Journal of Renewable Materials 2023, 11(9), 3485-3500. https://doi.org/10.32604/jrm.2023.027592

Received 05 November 2022; Accepted 05 December 2022; Issue published 20 July 2023

Abstract

The measures of steam curing and early-strengthening agents to promote the precast components to reach the target strength quickly can bring different degrees of damage to the concrete. Based on this, the new nanomaterial CSH-the hydration product of cement effectively solves these measures’ disadvantages, such as excessive energy consumption, thermal stress damage, and the introduction of external ions. In this paper, the effect of CSH on the early strength of precast fly ash concrete components was investigated in terms of setting time, workability, and mechanical properties and analyzed at the microscopic level using hydration temperature, XRD, and SEM. The results showed that under the same workability, CSH could significantly reduce the amount of admixture, shorten the final setting time, almost not affect the initial setting time, and accelerate the hydration of cement. At the optimum dose of 5%, the mechanical properties of the specimens were improved by more than 98% within 12 h of hydration, resulting in an earlier release time of 12 h and no risk of strength inversion later. The results of this paper give theoretical support to the behavior of precast components under steam-free curing.

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Keywords

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