Effect of New Hardening Accelerator on the Strength of Segment Concrete

Abstract

A novel crystal nucleus-based cement-hardening accelerator was evaluated using various mortar and segment concrete experiments. The mechanism of hardening acceleration was investigated via hydration temperature variation analysis, hydration degree analysis, X-ray diffraction (XRD) and scanning electron microscopy (SEM). In the presence of accelerator, the fluidity loss of mortar was increased after 30 minuites, and a coagulation was also observed. Moreover, based on the image of SEM, the formation of C-S-H gels was enhanced in the early hydration. As a result, the hardening accelerator could significantly boost the early strength of concrete, especially within one day of pouring, and shorten steam curing time to meet the demolding strength.

Keywords

crystal nucleus / hardening accelerator / C-S-H / hydration / strength

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