Hydration mechanism of a cementitious material prepared with Si-Mn slag

Xu-fang Zhang1,2), Wen Ni1), Jun-yu Wu3), and Li-ping Zhu1) 1) Key Laboratory of the Minstry of Education of China for High-Efficient Mining and Safety of Metal Mines Ministry of Education, University of Science and Technol-ogy Beijing, Beijing 100083, China 2) North China University of Water Resources and Electric Power, Zhengzhou 450011, China 3) Beijing Dongfangjianyu Institute of Concrete Science and Technology, Beijing 100190, China

摘 要：A cementitious material was prepared by mixing 80wt% Si-Mn slag powder, 10wt% lime, and 10wt% anhydrite. The compressive strength of mortar samples reaches 51.48 MPa after 28 d curing. The analyses of X-ray diffraction （XRD） and scanning electron microscopy （SEM） show that much ettringite is formed in the sample cured for 3 d, and C-S-H gel increases rapidly during subsequent curing. Nuclear magnetic resonance （NMR） analysis of 29Si and 27Al and infrared spectroscopy （IR） analysis show that aluminum decomposition from tetrahedral network of the slag glass and its subsequent migration and re-combination play an important role in the process of hydration and strength development of the samples.

关键词：