Title: Absolute Volume Change of Portland Cement Studied by Helium Pycnometry

Author(s): Zhenping Sun, Xu Yang, Juntao Tian, Haijing Yang, Yanliang Ji, and Kuangyi Hu

Publication: Symposium Paper

Volume: 330

Issue:

Appears on pages(s): 21-30

Keywords: Helium pycnometry; Hydration process; Absolute volume change

DOI: 10.14359/51711237

Date: 9/26/2018

Abstract:
Based on detection technology of helium pycnometry, the study developed a novel approach for studying absolute volume change of Portland cement in early-age hydration process. Traditional methods, such as heat evolution, chemical shrinkage test (ASTM C 1608) and X-ray diffraction (XRD), were also adopted for comparison and analyzation. Results indicated that helium pycnometry is quite suitable in the study of the absolute volume change of Portland cement. Compared with chemical shrinkage test, the data captured by helium pycnometry is more accurate and efficient for analyzing the absolute volume change of Portland cement. Meanwhile, helium pycnometry is found to have a good correspondence with the traditional methods, the trends of which are almost the same. According to the trends of the absolute volume change and heat flow, hydration process of Portland cement can be divided into five stages, which are dissolution stage, induction stage, acceleration stage, deceleration stage and stable stage.