Research on the internal pores in alkali-activated slag cementing material via X-CT three-dimensional imaging microscopy

Abstract

Research on the ability of chlorine resistance and sulfur resistance of the concrete with different water to binder ratios AIP Conference Proceedings 1794, 020002 (2017) Abstract. X-Ray computed tomography (X-CT) three-dimensional imaging microscopy was used to scan the test specimens made with hardening alkali-activated slag cementing material, and the distribution and morphology characteristics of internal micron pores were obtained accurately; meanwhile the test specimens at the age of 1 day, 7 days, 14 days and 28 days were also scanned, and the data collected by X-CT were processed accordingly by use of images and data processing software Avizo for three-dimensional reconstruction study and comparison on the change conditions of internal pores. The experimental results showed that the proportion of micron pores firstly increased and then decreased, the pore volume was basically stable over the age of 14 days, and the diameter of most pores was 200μm or less.

Durability of Concrete With Coal Gasification Slag and Coal Gangue Powder

“…The structure of cement mortar is complex, and the size of the internal pores has a large span. Bout et al roughly divide the pore size into four categories and give the impact of each level of pores on the performance: the gel pore, with pore size of less than 20 nm (harmless pore); the transition pore, with diameter in the range of 10-100 nm (less harmful pores); the capillary pore, with diameter in the range of 100-1000 nm (harmful pores); and the macro pores, with pore size of greater than 1000 nm (Long et al, 2017). Figures 5-7 exhibit the pore structure of concrete at different ages.…”