Title:
Degradation Process of Cementitious Materials with Copper Slag Subjected to Sodium Sulfate Attack under Drying-Wetting Cycles
Author(s):
Huashan Yang and Yujun Che
Publication:
Symposium Paper
Volume:
330
Issue:
Appears on pages(s):
1-10
Keywords:
cementitious materials; copper slag; sodium sulfate; hydration products; pore structure
DOI:
10.14359/51711235
Date:
9/26/2018
Abstract:
This paper presents an experimental study on the degradation process of cementitious materials with copper slag subjected to sodium sulfate attack under drying-wetting cycles. The cement pastes with 30% of copper slag (CS) were prepared by using water to binder ratio of 0.4. The degradation process of cementitious materials with copper slag immersed in 5% sodium sulfate solution under drying-wetting cycles were studied. X-ray diffraction (XRD) and backscattered electron image (BSE) were used to investigate microstructure changing. The research results indicate that the newly formed hydration products of partially reacted clinker increase the compactness of the hardened cementitious materials and increase the concentration of calcium hydroxide in the pore solution, thereby retarding the decomposition of C-S-H.
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