Design and performance optimization of alkali-activated waste coal bottom ash/slag porous concrete. (12th December 2022)

• Record Type: Journal Article
• Authors: Tan, Yi; He, Yan; Cui, Xuemin; Liu, Leping
• Is Part Of: Construction & building materials. Volume 359(2022)
• Publication Date: 2022-12-12
• Subjects: Porous concrete -- Rheological properties -- Alkali-activated materials -- Coal bottom ash (CBA) -- Compressive strength -- Paste film thickness (PFT); Building materials -- Periodicals; 624.18
• DOI: 10.1016/j.conbuildmat.2022.129413
• Languages: English
• ISSNs: 0950-0618

Abstract

Highlights: The effect of coal bottom ash content on the properties of AACS-PC of the paste was investigated. The fluidity and porosity of the paste were positively correlated with the coal bottom ash content. Using CBA as a mineral admixture to improve the rheological properties of alkali-activated slag pastes is feasible. The properties of AACS-PC could meet the requirements of the standard of ASTM and JISA. Abstract: When alkali-activated slag material is used in porous concrete, it has the problems of short setting time and poor operability. In this paper, the effect of coal bottom ash content on the rheological properties, the mechanical properties, porosity, permeability coefficient, and PFT of AACS-PC of the paste was investigated. The results showed that the fluidity and porosity of the paste with a water–solid ratio of 0.35 were positively correlated with the coal bottom ash content, but negatively correlated with the PFT. When the content of coal bottom ash was 20 wt% and the waterglass modulus was 1.4, the compressive strength of AACS-PC can reach 22.1Mpa and the water permeability coefficient of AACS-PC was 2.9 mm/s. Both the compressive strength and water permeability coefficient could meet the requirements of the standard of ASTM and JIS A. The addition of CBA can effectively improve the operability of alkali -activated materials in the preparation of porous concrete.