Title
Effects of GBFS content and curing methods on the working performance and microstructure of ternary geopolymers based on high-content steel slag
Author
Yang, Xinkui (Wuhan University of Technology)
Wu, Shaopeng (Wuhan University of Technology)
Xu, S. (TU Delft Materials and Environment; Wuhan University of Technology) 
Chen, B. (TU Delft Materials and Environment)
Chen, Dongyu (Wuhan University of Technology)
Wang, Fusong (Huazhong University of Science and Technology)
Jiang, Jian (Shenzhen Sez Construction Group Co., Ltd.)
Fan, Lulu (Shenzhen Sez Construction Group Co., Ltd.)
Tu, Liangliang (Shenzhen Sez Construction Group Co., Ltd.)
Date
2023
Abstract
Aimed to address the low utilization rate of steel slag (SS) and its challenge in resource utilization in China, this study developed ternary geopolymers made by high-content (50%) SS together with fly ash (FA) and granulated blast furnace slag (GBFS). The effects of GBFS content (0–40%) and curing methods (water curing, standard curing, sealed curing, and heat curing) on the working performance and microstructure of geopolymers were investigated. Microscopic analysis such as X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TG-DTG), and scanning electron microscopy (SEM) were utilized to investigate the hydration process and products of geopolymers under different curing conditions and GBFS content. The results indicated that when the GBFS content increased from 0% to 40%, the fluidity of the mixture decreased by 11.7%, the initial setting time of the geopolymer slurry decreased by 76%, and the geopolymer mortar's 28d compressive strength increased from 31.9 MPa to 60.6 MPa. At room temperature, the geopolymer mortar's 28d compressive strength was higher under standard curing (70.8 MPa) compared to water curing (57.5 MPa) and sealed curing (68 MPa). The geopolymer mortar cured at 60 °C for 24 h exhibited the highest 28d compressive strength (76.3 MPa). However, excessively high curing temperatures or prolonged durations led to more shrinkage cracks and reduced the compressive strength. The microscopic analysis revealed that the main gel products of ternary geopolymer were C-(A)-S-H gel. The amount of gel products is directly related to the strength of geopolymers. The developed ternary geopolymer has the potential to promote the large-scale utilization of SS in the concrete industry, making a significant contribution to sustainable development.
Subject
Curing methods
Geopolymer
Steel slag
Working performance
To reference this document use:
http://resolver.tudelft.nl/uuid:a07ff354-3da9-4e83-9a46-3b246736232e
DOI
https://doi.org/10.1016/j.conbuildmat.2023.134128
Embargo date
2024-05-21
ISSN
0950-0618
Source
Construction and Building Materials, 410
Bibliographical note
Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.
Part of collection
Institutional Repository
Document type
journal article
Rights
© 2023 Xinkui Yang, Shaopeng Wu, S. Xu, B. Chen, Dongyu Chen, Fusong Wang, Jian Jiang, Lulu Fan, Liangliang Tu