摘要
针对半水磷石膏凝结时间过快的问题,选取五种典型缓凝剂——柠檬酸、酒石酸、骨胶、葡萄糖酸钠及三聚磷酸钠,探究不同掺量的缓凝剂对半水磷石膏浆体标准稠度用水量、凝结时间和硬化体抗压强度、水化放热的影响。结果表明:掺入的五种缓凝剂都可以在不同程度上延长半水磷石膏的初凝时间、终凝时间,减少半水磷石膏的标准稠度用水量;在0.1%的低掺量情况下,缓凝效果最好的是酒石酸和葡萄糖酸钠,初凝时间、终凝时间都达到了未加入缓凝剂的空白试样的六倍以上,且3 d、7 d龄期下强度损失率均在20%~30%之内;其中葡萄糖酸钠可使峰值放热速率降低22.1%,峰值速率出现时间延长一倍以上。综合考虑,酒石酸和葡萄糖酸钠可以延长半水磷石膏的凝结时间,降低水化放热速率,且硬化体的强度损失率较低。
In order to solve the problem of too fast setting time of hemihydrate phosphogypsum,five typical retarders-citric acid,tartaric acid,bone glue,sodium gluconate and sodium tripolyphosphate were selected to explore the effects of different amount of retarder on the water consumption of standard consistency,setting time,compressive strength and hydration heat release of hemihydrate phosphogypsum paste.The results showed that the five retarders can prolong the initial setting time and final setting time of hemihydrate phosphogypsum and reduce the water consumption of standard consistency of hemihydrate phosphogypsum.In the case of 0.1%low content,tartaric acid and sodium gluconate have the best retarding effect,and the initial setting time and final setting time are more than 6 times that of the blank sample without retarder,and the strength loss rate is less than 20%to 30%in 3 d and 7 d.Among them,sodium gluconate can reduce the peak heat release rate 22.1%,and the occurrence time of the peak rate is more than doubled.Considering comprehensively,tartaric acid and sodium gluconate can prolong the setting time of hemihydrate phosphogypsum,reduce the hydration heat release rate,and the strength loss rate of hardened body is lower.
作者
王嘉昊
沈玉
刘娟红
罗昆
WANG Jiahao;SHEN Yu;LIU Juanhong;LUO Kun(School of Civil and Resource Engineering,University of Science and Technology Beijing,Beijing 100083,China;The Third Engineering Co.,Ltd.,CCCC Second Highway Engineering Co.,Ltd.,Xi'an 710016,China;Beijing Key Laboratory of Urban Underground Space Engineering,University of Science and Technology Beijing,Beijing 100083,China;Key Laboratory of Ministry of Education for Efficient Mining and Safety of Metal Mines,University of Science and Technology Beijing,Beijing 100083,China)
出处
《材料导报》
EI
CAS
CSCD
北大核心
2022年第S01期262-266,共5页
Materials Reports
基金
国家自然科学基金(51834001)
中央高校基本科研业务费(FRF-BD-20-01A,FRF-BD-20-01B)
关键词
半水磷石膏
缓凝剂
凝结时间
强度损失
水化热
hemihydrate phosphogypsum
retarder
coagulation time
strength loss
heat of hydration
