摘要
碱-矿渣水泥目前常用缓凝剂延长凝结时间,但缓凝剂存在用量不宜控制、缓凝效果受温度影响较大、影响早期强度等问题。本研究采用一种缓释型碱激发剂对其凝结时间进行调节。实验采用不同总质量的环氧树脂包覆处理水玻璃,得到不同厚度的环氧树脂覆膜,研究了不同覆膜厚度的激发剂对碱-矿渣水泥凝结时间、力学性能、微观性能的影响。实验表明,使用环氧树脂覆膜于激发剂表面后,能显著延长碱-矿渣水泥的凝结时间,其中100%包裹组将初凝时间延长了90%;环氧树脂的加入提高了水泥的1 d强度,75%包裹组1 d强度提高了54.02%;环氧树脂对28 d的抗压强度贡献不大,但能提高试件的韧性,25%包裹组的压折比降低了10.18%;环氧树脂以覆膜形式加入碱-矿渣水泥中较直接以外加剂加入更能促进基体的水化进程。
Alkali-slag cement has the defects of setting time too fast and unconvenience for engineering construction.The common method to prolong setting time is to add retarder,but there are a series of problems,such as uncontrollable dosage of retarders,great influence of temperature on retarding effect,and influence on early strength.To solve this problem,a kind of slow-release alkali activator is proposed to adjust the setting time of alkali-slag cement.By using different masses of epoxy resin to coat sodium silicate,epoxy resin coatings with different thicknesses were obtained,and the effects of activator with different thickness on setting time,mechanical properties and microscopic properties of alkali-slag cement were studied.The results show that the setting time of the alkali-slag cement slurry can be significantly prolonged by using epoxy resin as the coating material on the activator surface,and the initial setting time of the 100%coating group can be extended by 90%.The addition of epoxy resin can improve the 1 d strength of cement,and the 1 d strength of 75%coated group is increased by 54.02%compared with that of blank group.Epoxy resin does not contribute much to the compressive strength at the 28 d,but it can improve the toughness of the specimen.The folding ratio of 25%coating group is reduced by 10.18%.Epoxy resin added in the form of film coating to alkali slag cement can promote the hydration process of matrix better than additives added directly.
作者
冯春花
崔卜文
刘宇豪
贾旭赫
张文艳
朱建平
FENG Chunhua;CUI Buwen;LIU Yuhao;JIA Xuhe;ZHANG Wenyan;ZHU Jianping(School of Materials Science and Engineering,Henan Polytechnic University,Jiaozuo 454000,China)
出处
《材料科学与工程学报》
CAS
CSCD
北大核心
2023年第2期254-259,共6页
Journal of Materials Science and Engineering
基金
河南省科技厅科技攻关资助项目(212102310566,182102310889)
国家自然科学基金资助项目(51908198)。
关键词
碱-矿渣水泥
环氧树脂
缓释
凝结时间
力学性能
微观结构
Alkali-slag cement
Epoxy resin
Slowing release
Setting time
Mechanical properties
microstructure
