粉煤灰性质对微波加热碱激发材料强度发展的影响
作者:
作者单位:

1.西安建筑科技大学 材料科学与工程学院,陕西 西安 710055;2.西安建筑科技大学 教育部 生态水泥工程研究中心,陕西 西安 710055;3.西安建筑科技大学 陕西省生态水泥混凝土 工程技术研究中心,陕西 西安 710055

作者简介:

朱绘美(1986—),女,山东泰安人,西安建筑科技大学副教授,硕士生导师,博士.E-mail: zhuhuimeitj@163.com

通讯作者:

李 辉(1971—),女,河南三门峡人,西安建筑科技大学教授,博士生导师,博士. E-mail: sunshine_lihui@126.com

中图分类号:

TQ536.4

基金项目:

固废资源化利用与节能建材国家重点实验室开放基金资助项目(SWR-2021-009); 陕西省重点研发计划项目(2023-YBGY-498);陕西省教育厅重点研发计划(20JS079);先进土木工程材料教育部重点实验室(同济大学)开放基金资助项目(202104)


Effect of Fly Ash Properties on Strength Development of Microwave-Heated Alkali-Activated Binder
Author:
Affiliation:

1.College of Materials Science and Engineering, Xi'an University of Architecture and Technology, Xi'an 710055,China;2.Ecological Cement Engineering Research Center of Ministry of Education, Xi'an University of Architecture and Technology, Xi'an 710055,China;3.Shaanxi Ecological Cement & Concrete Engineering Technology Research Center, Xi'an University of Architecture and Technology, Xi'an 710055,China

Fund Project:

  • 摘要
  • |
  • 图/表
  • |
  • 访问统计
  • |
  • 参考文献
  • |
  • 相似文献
  • |
  • 引证文献
  • |
  • 资源附件
  • |
  • 文章评论
    摘要:

    以Ca含量和细度不同的粉煤灰制备碱激发粉煤灰(AAFA)胶凝材料,并在水化早期对其进行微波加热养护,研究其抗压强度和微观结构的发展规律,探讨微波加热养护对强度发展的影响机理.结果表明:增加粉煤灰的Ca含量及适当减小粉煤灰的细度均可显著提高微波加热养护后AAFA试件的抗压强度,但会加剧其28 d龄期后的强度倒缩;水化硅(铝)酸钙(C-(A)-S-H)凝胶中的Ca2+溶出后碳化形成致密度较差的海绵状凝胶、水化硅铝酸钠(N-A-S-H)凝胶分解及其体积缩小均是引起微波加热养护后AAFA试件强度倒缩的原因;由超细粉煤灰(D50=3.96 μm)制备的AAFA试件呈现出远低于基准试件的抗压强度,不适合采用微波加热养护.

    Abstract:

    Alkali-activated fly ash(AAFA) binders were prepared from fly ash with different calcium content and fineness, and were cured by microwave heating at the early stage of hydration. The developments of compressive strength and microstructure of AAFA specimens were studied and the influence mechanism of microwave heating on strength development was discussed. The results show that increasing the calcium content in fly ash and appropriately reducing the fineness of fly ash can significantly improve the compressive strength of AAFA specimens after microwave heating, but aggravate the strength loss after 28 d. The reason for the strength loss of AAFA specimens cured by microwave heating lies in the dissolution and carbonation of calcium ions in aluminum-modified calcium silicate hydrate(C-(A)-S-H) gel, resulting in the formation of sponge like gel with low density and the decomposition and volume reduction of sodium aluminosilicate hydrate(N-A-S-H) gel. The compressive strength of AAFA specimens prepared from ultrafine fly ash (D50=3.96 μm) is much lower than that of the reference specimen, therefore the former is not suitable for microwave-heated curing.

    参考文献
    相似文献
    引证文献
引用本文

朱绘美,迂晨,张新东,乔沛,李辉.粉煤灰性质对微波加热碱激发材料强度发展的影响[J].建筑材料学报,2023,26(5):449-456

复制
分享
文章指标
  • 点击次数:
  • 下载次数:
  • HTML阅读次数:
  • 引用次数:
历史
  • 收稿日期:2022-03-19
  • 最后修改日期:2022-05-30
  • 录用日期:
  • 在线发布日期: 2023-06-08
  • 出版日期: