Calcium leaching resistance of cement composites with liquid-crystal display glass powder

• Published in: Journal of Building Engineering 2024-08, Vol.91, p.109607, Article 109607
• Main Authors: Lee, Yujin, Seo, Seunghoon, Doh, Jeung-Hwan, You, Ilhwan, Zi, Goangseup
• Format: Article
• Language: English
• Subjects: Calcium leaching; Concrete durability; Fly ash; Glass powder; Liquid-crystal display glass
• ISSN: 2352-7102; 2352-7102
• DOI: 10.1016/j.jobe.2024.109607

This study explores the calcium leaching resistance of cement composite with liquid-crystal display glass powder (LCDGP). Authors compare LCDGP with other pozzolanic materials, fly ash and soda-lime glass powder, replacing 20% of the cement. Results show that LCDGP reduces the leaching rate by 47.2% and hardness degradation depth by 28.6%, compared to the fly ash-blended mixture. High pozzolanic reactivity of LCDGP lowers the initial calcium hydroxide and total porosity including a decreased volume of pores exceeding the capillary pore size, resulting in a dense microstructure. Consequently, these effectively delay calcium hydroxide dissolution and calcium-silicate-hydrate decalcification. LCDGP-blended mixture shows the decreased C-S-H gel decalcification depth by 21.4% and exhibits 28.6% less hardness reduction depth compared with fly ash-blended mixture. Based on these findings, authors advocate the potential application of LCDGP as an admixture for concrete structures that are exposed to water. [Display omitted] •LCDGP augments the resistance to calcium leaching of cement composites.•LCDGP20 reduced the leaching depth by 16.3% and rate by 47.2% compared with FA20.•LCDGP reduced C-S-H gel decalcification depth and hardness reduction depth.•High pozzolanic reactivity of LCDGP reduces the initial calcium hydroxide content.