矿渣对复合胶凝材料硬化浆体微观结构的影响

矿渣对复合胶凝材料硬化浆体微观结构的影响

韩方晖¹，刘仍光²，阎培渝²

（1.中国矿业大学(北京)化学与环境工程学院 北京 100083；2.清华大学土木工程系，

土木工程安全与耐久教育部重点实验室，北京100084)

摘 要： 利用XRD和SEM对掺矿渣复合胶凝材料硬化浆体微观结构进行了研究，结果显示: 矿渣的掺入使胶凝材料中水泥的质量分数下降，矿渣反应消耗部分Ca(OH)₂，导致硬化浆体中Ca(OH)₂的含量降低，2 a龄期时掺70%矿渣样品中仍有Ca(OH)₂存在。矿渣掺入后，硬化浆体的早期微观结构会较为疏松，随着养护龄期的延长，大量低Ca/Si的C-S-H凝胶生成， 使复合胶凝材料硬化浆体逐渐致密，且凝胶中含Al较多。

关键词：矿渣；微观结构；XRD；SEM；C-S-H凝胶

      中图分类号：TU528；TG115.21⁺5.3；TH842；TG115.23         文献标识码：A    doi:10.3969/j.1000-6281.2014.01.007

Influence of slag on microstructure of complex binder pastes

HAN Fang-hui¹，LIU Reng-guang²，YAN Pei-yu²

（1.School of Chemical and Environmental Engineering, China University of Mining and Technology (Beijing), Beijing 100083; 2.Key Laboratory of Civil Engineering Safety and Durability of China Education Ministry, Department of Civil Engineering, Tsinghua University, Beijing 100084, China）

Abstract: The microstructure of cement-slag complex binder pastes was investigated by means of XRD and SEM. The results show that the cement content in complex binder decreased with slag content and the reaction of slag consumed some Ca(OH)₂, so Ca(OH)₂ content decreased with slag content in complex binder pastes. The Ca(OH)₂ crystal still exists in the complex binder pastes containing 70% content slag at the age of 2 years. By replacing part of cement with slag，the early microstructure of complex binder pastes becomes loosened. With the increase of curing ages, a great quantity of C-S-H gel with low Ca/Si ratio are generated in the complex binder pastes with slag and the gel contains much Al, which makes the hardened complex binder pastes denser gradually.

Keywords: slag; microstructure; X-ray diffraction; scanning electron microscope; C- S- H gel

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