长江科学院院报 ›› 2021, Vol. 38 ›› Issue (1): 146-150.DOI: 10.11988/ckyyb.20191066

• 水工结构与材料 • 上一篇    

煅烧渣土-白云石对水泥砂浆强度和膨胀性能的影响

陈登1,2, 宋旭艳1, 何智海3   

  1. 1.苏州科技大学 土木工程学院,江苏 苏州 215011;
    2.长江科学院 水利部水工程安全与病害防治工程技术研究中心,武汉 430010;
    3.绍兴文理学院 土木工程学院,浙江 绍兴 312000
  • 收稿日期:2019-09-04 修回日期:2020-01-15 出版日期:2021-01-01 发布日期:2021-01-27
  • 作者简介:陈 登(1988-),男,江苏盐城人,讲师,博士,主要从事混凝土材料方面的研究。E-mail: deng2928326@163.com
  • 基金资助:
    长江科学院开放研究基金资助项目(CKWV2019757/KY);国家自然科学基金项目(51778003);广西建筑新能源与节能重点实验室开放课题项目(19-J-22-1);江苏省建设系统科技项目(2017ZD23)

Effects of Calcined Muck-Dolomite on Strengths and Expansion Properties of Cement Mortar

CHEN Deng1,2, SONG Xu-yan1, HE Zhi-hai3   

  1. 1. College of Civil Engineering, Suzhou University of Science and Technology, Suzhou 215011, China;
    2. Research Center of Water Engineering Safety and Disaster Prevention of Ministry of Water Resources,Yangtze River Scientific Research Institute, Wuhan 430010, China;
    3. College of Civil Engineering,Shaoxing University, Shaoxing 312000, China
  • Received:2019-09-04 Revised:2020-01-15 Online:2021-01-01 Published:2021-01-27

摘要: 采用渣土对白云石进行煅烧改性,研究了煅烧渣土-白云石对水泥砂浆强度和膨胀性能的影响规律,并采用X射线衍射仪、扫描电子显微镜和能谱仪研究了掺煅烧渣土-白云石水泥的水化产物性能。结果表明:煅烧渣土-白云石可生成β-C2S和C12A7,且随着煅烧温度的提高,β-C2S和C12A7的含量增加;煅烧渣土-白云石能够有效促进复合水泥砂浆后期强度的发展,其中掺10%煅烧渣土-白云石水泥砂浆的90 d强度甚至高于纯水泥砂浆;此外,煅烧渣土-白云石中的MgO可水化生成Mg(OH)2,固相体积增加,促进了水泥砂浆的膨胀,且膨胀率随着煅烧渣土-白云石掺量的增加而增加。研究成果对于提高白云石在水泥混凝土中的应用及减轻建筑垃圾对环境的污染有一定参考价值。

关键词: 渣土, 白云石, 煅烧, 水泥砂浆强度, 膨胀性能

Abstract: Dolomite was modified through calcination mixed with muck. The effects of calcined muck-dolomite on the strength and expansion properties of cement mortar were investigated. The hydration products of cement containing calcined muck-dolomite were examined by X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive spectrometer (EDS). Results show that β-C2S and C12A7 were generated in calcined muck-dolomite, and the content of β-C2S and C12A7 increased with the rising of calcination temperature. The incorporation of calcined muck-dolomite improves the strengths of blended cement mortar effectively at later age. Cement mortar containing 10% calcined muck-dolomite even gain a higher strength at 90 d than pure cement mortars. In addition, the hydration of MgO in calcined muck-dolomite gave rise to Mg(OH)2, resulting in the expansion of cement mortars, and the expansion rate augmented with the increase of dosage of calcined muck-dolomite. The research finding is of referential value for promoting the application of dolomite in cement concrete and for reducing the pollution of construction wastes.

Key words: muck, dolomite, calcination, strength of cement mortar, expansion properties

中图分类号: