Durability of Green Concrete in Severe Environment

Yonggan Yang^1,2,3,4, Zihao Kang¹, Binggen Zhan^1,3,*, Peng Gao^1,3,*, Qijun Yu¹, Yanlai Xiong⁴, Jingfeng Wang^1,3, Yunsheng Zhang⁵
1 School of Civil Engineering, Hefei University of Technology, Hefei, 230009, China
2 Henan Key Laboratory of Materials on Deep-Earth Engineering, Henan Polytechnic University, Jiaozuo, 454000, China
3 Anhui Key Laboratory of Civil Engineering Structure and Materials, Hefei University of Technology, Hefei, 230009, China
4 Hefei Cement Research and Design Institute Co., Ltd., Hefei, 230051, China
5 College of Civil Engineering, Lanzhou University of Technology, Lanzhou, 730050, China
* Corresponding Authors: Binggen Zhan. Email: zhanbgpaper@163.com; Peng Gao. Email: gaop@hfut.edu.cn

Journal of Renewable Materials https://doi.org/10.32604/jrm.2023.025059

Received 19 June 2022; Accepted 22 August 2022; Published online 30 September 2022

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Abstract

In this paper, the effects of different mineral admixtures and sulfate solution types on the appearance, mass change rate, relative dynamic elastic modulus, and corrosion resistance coefficient of concrete were systematically studied. X-ray Diffraction (XRD), Mercury Intrusion Porosimetry (MIP), Scanning Electron Microscopy (SEM), and X-ray Computed Tomography (X-CT) were used to explore and analyze the changes in the microstructure and the corrosion products of concrete in the sulfate solution. The results show that the existence of magnesium ions accelerates concrete deterioration. There is a critical dosage of fly ash for magnesium sulfate resistance of concrete. The magnesium sulfate resistance of concrete is improved when the fly ash content is less than 20%. Slag can significantly improve the corrosion resistance of concrete to magnesium sulfate. The diffusion of sulfate ions into concrete is a gradual process. In the early stages of corrosion, sulfate ion content in the concrete immersed in the magnesium sulfate solution is slightly less than that of the concrete immersed in the sodium sulfate solution. However, in the later stage of corrosion, the sulfate ion content in the concrete immersed in the magnesium sulfate solution is significantly higher than that of the concrete immersed in the sodium sulfate solution.