粉煤灰对水泥与聚羧酸减水剂相容性的影响  

Effect of Fly Ash on Compatibility of Cement with Polycarboxylate Superplasticizer

作　　者：赵明明 欧志华[1] 黄文峰 ZHAO Mingming;OU Zhihua;HUANG Wenfeng(School of Civil Engineering,Hunan University of Technology,Zhuzhou 412007,China;Hunan Shengfeng new material Technology Co.,Ltd.,Changsha 410100,China)

机构地区：[1]湖南工业大学土木工程学院,湖南株洲412007 [2]湖南盛峰斯邦新材料科技有限公司,湖南长沙410100

出　　处：《上海建材》2024年第2期74-77,共4页Shanghai Building Materials

摘　　要：水泥与减水剂相容性差会导致混凝土急凝、坍落度经时损失大和离析泌水等情况,粉煤灰的掺加会影响水泥与减水剂的相容性。试验结果表明:随着减水剂掺量的增加,在0.29和0.23这2种水胶比下,基准水泥与减水剂的相容性比硅酸盐水泥与减水剂的相容性好,并且水胶比大混凝土的流动性较好,故水胶比为0.29时,基准水泥与减水剂的相容性更好;粉煤灰的掺加改变了减水剂掺量、饱和掺量点和离析点,适量的粉煤灰掺量可以改善水泥与高效减水剂的相容性,考虑到浆体的初始流动度和流动度经时损失,粉煤灰的最佳掺量为30%;相对于粉煤灰FA1,粉煤灰FA2的饱和掺量点低,60 min净浆流动度经时损失小,故FA2对水泥与减水剂相容性的改善效果更明显。The poor compatibility of cement and water-reducing agent will lead to the loss of concrete slump and segregation of water,while the addition of fly ash will affect the compatibility of cement and water-reducing agent.The experiment results show that with the increase of the content of water⁃reducing agent,when the ratio of water to cement is 0.29 and 0.23,the compatibility between standard cement and water reducing agent is better than that between Portland cement and water reducing agent.When the ratio of water to cement was greater,the fluidity was better.Therefore,it can be concluded that the compatibility between standard cement and water⁃reducing agent is better when the ratio of water to cement is 0.29.The continuous addition of fly ash would change the content of superplasticizer,saturation content point and segregation point.The compatibility between cement and superplasticizer could be improved with an appropriate amount of fly ash.Considering the initial fluidity and the loss of fluidity of slurry,the optimal content of fly ash was determined to be 30%.Compared with FA1,the saturation content point of FA2 was lower,and the flow loss of 60 min clean slurry was small,indicating that the compatibility between cement and water reducer can be improved more effectively by FA2.

关 键 词：水泥 聚羧酸减水剂 相容性 粉煤灰 

分 类 号：TU528[建筑科学—建筑技术科学]