摘要
In the present study, chemical mapping on the hydration process of cement paste with water-to-cement (w/c) ratio of 0.60 was implemented by Raman spectroscopy (RS). The RS was applied to study the paste from 12 hours after mixing to 28 days. Cement ingredients and hydration products, including calcium silicates (C3S and C2S), calcium hydroxide (CH), and ettringite, were quantitatively studied. From the research, it is observed that calcium silicates were consumed gradually with the increased hydration age. Calcium hydroxide increased and tended to cluster in the pore vicinity during hydration. Ettringite was found to form on the surface of the unreacted particles, which was shown as a mixed zone of ettringite and calcium silicates in the maps. It is concluded from the study that chemical mapping was an effective method to assist in visualizing particle dispersion and connection on top of the quantitative analysis.
In the present study, chemical mapping on the hydration process of cement paste with water-to-cement (w/c) ratio of 0.60 was implemented by Raman spectroscopy (RS). The RS was applied to study the paste from 12 hours after mixing to 28 days. Cement ingredients and hydration products, including calcium silicates (C3S and C2S), calcium hydroxide (CH), and ettringite, were quantitatively studied. From the research, it is observed that calcium silicates were consumed gradually with the increased hydration age. Calcium hydroxide increased and tended to cluster in the pore vicinity during hydration. Ettringite was found to form on the surface of the unreacted particles, which was shown as a mixed zone of ettringite and calcium silicates in the maps. It is concluded from the study that chemical mapping was an effective method to assist in visualizing particle dispersion and connection on top of the quantitative analysis.
基金
Acknowledgements The financial supports from the National Science Foundation (CMMI-1265983), the Department of Civil and Environmental Engineering, and the Graduate School Diversity Research Grant for Graduate Students (CODRE) at the University of Louisville, are highly appreciated. We also thank the Conn's Center for providing Raman spectroscopy. The authors also appreciate Dr. Chengqing Qi from CEMEX Technical Center for cement chemical composition analysis.