Quantitative Study of Concrete Mesostructure Based on Two-Phase Composition of Aggregate and Paste

Abstract

Abstract: Paste thickness or distance between aggregates is an important parameter in the study of concrete properties and the mix design of concrete, and its quantitative methods generally include two types of paste thickness models, the mean free path model and the image processing method. In this paper, the paste thickness and the mean free path of 24 concrete specimens were calculated and measured by the quantitative methods above, by comparing the differences and relationships of the quantitative results, the applicability of these methods was illustrated. The results show that the power functions can be regressed between the paste thickness obtained by different methods and the volume fraction of aggregate, and the linear relationships are observed between the paste thickness calculated and measured by different methods, which implies that all of these methods can be used to qualitatively analyze the relationship between concrete performance and mesostructure. By comparing the derivation process of the different quantitative models, a modified paste thickness model (MAPT_Ⅱ) is obtained, which has better convenience and precision than the maximum/average paste thickness (MPT/APT_Ⅰ) models.

Key words: concrete mesostructure, distribution of aggregate, quantitative method, paste thickness, free path between aggregates

CLC Number:

TU528

XU Haiming, XU Xiaoming, NIU Heyang, XU Gelong, CAI Jiwei, TIAN Qing. Quantitative Study of Concrete Mesostructure Based on Two-Phase Composition of Aggregate and Paste[J]. BULLETIN OF THE CHINESE CERAMIC SOCIETY, 2021, 40(6): 2011-2018.

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