Misestimation of the ITZ Thickness around Non-Spherical Aggregates

Abstract:

The ITZ (interfacial transition zone) in concrete has very high porosity and permeability, which affects concrete’s macroscopic mechanical properties and transport properties. Two-dimensional (2D) areal analysis and one-dimensional (1D) linear analysis are usually used to study ITZ’s microstructure. However, 3D microstructure is difficult to be characterized by 1D and 2D information. For example, 2D cross-section planes do not always intercept both the ITZ and the corresponding aggregate, which causes some ITZ regions are ignored by researchers. Therefore, ITZ’s volume and thickness will be misestimated, and leads to the misestimation of the diffusivity. In this paper, the effect of aggregate’s shape on the misestimation of ITZ thickness t is studied. The results reveal that the misestimation increases with the increasing sphericity s of aggregates.

• Periodical: Materials Science Forum (Volume 1036)
• Pages: 432-441
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.1036.432
• Online since: June 2021
• Authors: Ming Qi Li, Hui Su Chen*
• Keywords: Diffusivity, ITZ Thickness, Ovoidal Particles, Platonic Particles

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