院报 ›› 2018, Vol. 35 ›› Issue (7): 131-135.DOI: 10.11988/ckyyb.20170146

• 水工结构与材料 • 上一篇    下一篇

MgO活性对无机聚合物硬化浆体体积变形及微观结构的影响

李兆恒1a,1b,2, 杨永民1a,1b,2, 陈晓文1a,1b, 张君禄1a,1b, 余其俊2   

  1. 1.广东省水利水电科学研究院 a.结构材料研究所;b.广东省水利新材料与结构工程技术研究中心,广州 510635;
    2.华南理工大学 材料科学与工程学院, 广州 510640
  • 收稿日期:2017-02-20 出版日期:2018-07-01 发布日期:2018-07-12
  • 作者简介:李兆恒(1988-),男,山东济宁人,助理研究员,博士,主要从事镁基胶凝材料和碱激发胶凝材料的研究。E-mail:mszhaohengli@scut.edu.cn
  • 基金资助:
    广东省水利科技创新项目(2015-10);中国博士后科学基金(2016M590776)

Effects of MgO Activity on Volumetric Deformation and Microstructure of Hardened Geopolymer Pastes

LI Zhao-heng1,2,3, YANG Yong-min1,2,3, CHEN Xiao-wen1,2, ZHANG Jun-lu1,2, YU Qi-jun3   

  1. 1.Department of Structural Materials,Guangdong Research Institute of Water Resources and Hydropower,Guangzhou 510635, China;
    2.Guangdong Provincial Research Center on Water Conservancy New Materialsand Structural Engineering, Guangzhou 510635, China;
    3.School of Materials Science and Engineering,South China University of Technology, Guangzhou 510640, China
  • Received:2017-02-20 Online:2018-07-01 Published:2018-07-12

摘要: 无机聚合物胶凝材料是一种新型胶凝材料,具有早期强度快硬、结构致密的特点,且抗腐蚀性能优异,可应用于滨海和海洋工程基础设施建设。但该类材料存在收缩大、易开裂的缺陷,严重影响了其工程应用。结合无机聚合物快硬早期强度的特点,研究了高活性(60 s)、中活性(150 s)及低活性(220 s)氧化镁(MgO)对无机聚合物硬化浆体的体积变形及微观结构的影响。结果表明:MgO活性对无机聚合物性能影响显著,60 s活性MgO促进无机聚合物的水化放热,提高了无机聚合物硬化浆体的早期强度,且硬化浆体的早期收缩值最低,硬化浆体的改善效果也最好;150 s和220 s活性MgO延缓了无机聚合物水化放热,但改善了无机聚合物长龄期的体积收缩;MgO加入到无机聚合物中与水反应生成了Mg(OH)2,从而改善无机聚合物的体积收缩。

关键词: 无机聚合物, MgO活性, 体积变形, 水化进程, 基础设施, 胶凝材料

Abstract: Geopolymer, a novel cementitious material of superb corrosion resistance and quick setting and bigstrength in early stage, is applied to offshore and coastal projects. It is also, however, subject to cracking and large volume shrinkage which limit its engineering application. In this paper, the effects of MgO of high activity (60 s), medium activity (150 s) and low activity (220 s) on the volumetric shrinkage and microstructure of hardened geopolymer pastes were examined respectively. Results revealed remarkable influence of MgO activity on geopolymer performance: MgO of high activity could improve the early-stage strength of hardened geopolymer pastes by enhancing hydration heat release, and the early shrinkage value of the hardened pastes were the lowest; on the contrary, MgO of medium activity and low activity postponed the hydration heat release, and alleviated the volumetric shrinkage by acting with water in the geopolymer.

Key words: gopolymer, MgO activity, volumetric deformation, hydration process, infrastructure, binding material

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