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贺元启¹ ,  张    晖² ,  李    洋²

 

( 1. 浙江省石油股份有限公司 , 杭州   310050 ;

2. 长江水利委员会长江科学院 工程质量检测中心 , 武汉   430072)

摘  要 :  为探究粉煤灰对高碱含量水泥基材料早期收缩性能的影响程度及机制 , 选择 2 种类型碱和 2 种类型水泥基材料 , 利用相关检测技术 , 从水化进程 、孔结构及孔隙溶液离子含量角度揭示其影响机制 。结果表明 :粉煤灰抑制了低热水泥体系和普硅水泥体系由碱引起的干燥收缩和自收缩 , 其中对低热水泥体系收缩抑制作用大于普硅水泥体系 , 对掺 K2 SO4  引起的收缩抑制作用高于掺 Na2 SO4 。其抑制机制在于 ,  体系水泥含量降低对碱起到稀释作用 , 导致体系水化进程减缓 , 从而降低了水泥基材料早期收缩率 ; 不同类型碱对水泥基材料收缩性能的影响不同 , 与其水化产物孔结构参数的差异相关 。因此 , 粉煤灰更有利于降低低热水泥的收缩 , 更有利于降低含掺 K2 SO4  的水泥基材料收缩 , 在实际使用粉煤灰时 , 需关注水泥基材料类型和所含碱类型 , 研究结果可为相关项目提供参考

关键词 : 粉煤灰 ; 碱 ; 低热硅酸盐水泥 ; 收缩性能 ; 微观结构

中图分类号 : TV4          文献标志码 :  A           文章编号 :  1005- 8249  (2026)  03-0096-07

DOI :10. 19860/j. cnki. issn1005- 8249. 2026. 03. 016

 

HE Yuanqi¹ , ZHANG Hui² , LI Yang²

(1. Zhejiang Petroleum Co. , Ltd. ,  Hangzhou 310050 , China;

2. Engineering Quality Inspection Center ,  Changjiang River Scientific Research Institute ,

Wuhan 430072 , China)

Abstract :  To investigate the degree and mechanism of the influence of fly ash on the early shrinkage performance of high alkali content cement-based materials ,  two types of alkali and two types of cement-based materials were selected.   Relevant detection techniques were used to reveal the influencing mechanism from the perspectives of hydration process , pore  structure , and ion content of pore solution.   The  results  indicated that fly  ash inhibited the autogenous shrinkage and drying  shrinkage caused by alkali in both low -heat Portland cement  system and ordinary Portland cement  system.   Among  them ,  the  shrinkage  inhibition effect on low-heat Portland cement system was greater than that on ordinary Portland cement system , and it is more effective in suppressing  shrinkage   caused  by  potassium  sulfate  than  by  sodium  sulfate.   Mechanism  studies  had  shown  that  the  main  mechanism by which  fly  ash  inhibited  the  shrinkage  of  high  alkali cement - based  materials were : Fly ash dilutes alkali by reducing the cement content in the system , slows down the hydration process of the system , thereby reducing the early shrinkage rate of cement-based materials ; The influence of different types of alkali on the shrinkage performance of cement-based materials varies , which is related to the differences in pore structure parameters of their hydration products.   Therefore ,  fly  ash is more conducive to reducing the shrinkage of low heat cement and cement-based materials containing potassium sulfate.   When  using fly ash to suppress the shrinkage of cement-based materials in practice , attention should be paid to the type of cement-based material and the type of alkali it contains ,  The findings provide a reference for related projects.

Key words :  fly ash;  alkali ;  low-heat portland cement;  shrinkage property;  microstructure