High Content Of Fs New Cementitious Materials And Concrete Research

The application of fly ash and slag to building materials is not only advantageous to solving the question of environmental protection and energy conservation, comes to the new style which take 揺nvironmental materials?as main body. Moreover, it plays a positive role in improving the function of building materials especial materials?durability, extending the variety and use scope of building materials. Based on the full knowledge that fly ash and slag have regional differences in the aspect of their ingredient and potential activity, this article analyzed scientifically the specific property and investigated the way they would be utilized, which have important practical significance. Using special industrial waste fly ash and water-quenched slag as raw materials, the article started with studying the properties of the active materials, and selected proper compound activator to activate fully their hydration activity. Thereby, a new FS cement was researched and produced; it is different from conventional cement with less Portland cement clinker and simultaneously adding fly ash and slag with high volume. Furthermore, the article studied its applications to concrete. Through experiments, the compositions of different compound activators and the mix ratio of cements are confirmed. At the same time, the author researched the activating effect of different compound activators to fly ash and slag, tested physical constitution of cement hydrate by SEM, XRD and DTA etc., and analyzed hydration mechanism of cements. Researching the basic physical, mechanical performance and durability index of cements, it proved that the addition of slag can not only satisfy the basic physical and mechanical performance, but also advance the durability index and some other engineering properties. Researching the applications of FS cement to the concrete, the author thought that the addition of waste slag can satisfy concrete mechanical index and reduce concrete shrinkage. Through the researching and producing of this kind of materials, the author thought that it has better gelling property, accord with the cement test standard adopted at present ,as well as it has good flexural strength and durability property.