Structural evolution of binder gel in alkali-activated cements exposed to electrically accelerated leaching conditions

Solmoi Park; H N Yoon; Joonho Seo; H K Lee; Jeong Gook Jang

doi:10.1016/j.jhazmat.2019.121825

Structural evolution of binder gel in alkali-activated cements exposed to electrically accelerated leaching conditions

J Hazard Mater. 2020 Apr 5:387:121825. doi: 10.1016/j.jhazmat.2019.121825. Epub 2019 Dec 4.

Authors

Solmoi Park¹, H N Yoon², Joonho Seo², H K Lee², Jeong Gook Jang³

Affiliations

¹ Applied Science Research Institute, Korea Advanced Institute of Science and Technology, 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea; Department of Civil and Environmental Engineering, Korea Advanced Institute of Science and Technology, 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea.
² Department of Civil and Environmental Engineering, Korea Advanced Institute of Science and Technology, 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea.
³ Division of Architecture and Urban Design, Institute of Urban Science, Incheon National University, 119 Academy-ro, Yeonsu-gu, Incheon, 22012, Republic of Korea. Electronic address: jangjg@inu.ac.kr.

PMID: 31892426
DOI: 10.1016/j.jhazmat.2019.121825

Abstract

The structural evolution of a binder gel in alkali-activated cements exposed to accelerated leaching conditions is investigated for the first time. Samples incorporating fly ash and/or slag were synthesized and were exposed to electrically accelerated leaching by applying a current density of 5 A/m². The leaching behavior of the samples greatly depended on the binder gel formed in the samples. The N-A-S-H type gel abundant in fly ash-rich samples showed some extent of dissolution upon accelerated leaching, while slag-rich samples underwent hydration of the anhydrous slag after leaching. The obtained results are discussed in view of the degradation of the binder gel induced by accelerated leaching, and their potential performance under repository conditions where groundwater-induced leaching is the main durability concern.

Keywords: Accelerated leaching; Alkali-activated cements; Alkali-activated materials; Characterization; Radioactive waste repository.

Publication types

Research Support, Non-U.S. Gov't