The late-age strength and microstructure of mortar containing steel slag

Author(s): Qiang Wang, Peiyu Yan, Jianwei Yang
Paper category: Conference
Book title: 2nd International conference on Microstructural-related Durability of Cementitious Composites
Editor(s): Guang Ye, K. Van Breugel, Wei Sun, Changwen Miao
Print ISBN: 978-2-35158-129-2
e-ISBN: 978-2-35158-123-0
Publisher: RILEM Publications SARL
Pages: 1344- 1352
Total Pages: 8
Language: English

Steel slag has high contents of f-CaO and RO phase which may subsequently react with cement or water resulting in physical expansion, so the stability of steel slag is bad. The influence of steel slag on the late-age strength and microstructure of mortar was investigated in this study. The results show that the compressive strengths of mortars containing steel slag increase with hydration age, and they become closer to the compressive strength of pure cement mortar as the hydration age increases. The bad stability of steel slag does not have adverse effect on the late-age strength of mortar. The hardened cement-steel slag paste is very dense, and no obvious crack exists in the microstructure of mortar containing steel slag at late ages. RO phase and free CaO are the main factors that endow the steel slag bad stability. The unreacted RO phase particles are very easily to be observed in the hardened paste even at the age of 51 month. Part of free CaO in steel slag can react with water at very early ages. The RO phase with ultra low activity and free CaO with high activity do not have adverse effect on the volume stability of mortar.

Online publication: 2013
Publication Type: full_text
Public price (Euros): 0.00