胶凝材料用量对新拌自密实混凝土性能的影响  

Effect of Cementitious Material Content on Properties of Fresh Self-Compacting Concrete

作　　者：李方贤[1] 韦江雄[1] 王辉诚 王景平 裴新意 余其俊[1] 

机构地区：[1]华南理工大学材料科学与工程学院,广东广州510640 [2]中广核工程有限公司,广东深圳518124

出　　处：《华南理工大学学报（自然科学版）》2012年第4期79-84,共6页Journal of South China University of Technology(Natural Science Edition)

基　　金：国家"十二五"科技支撑计划项目(2011BAE27B02-3);广东省自然科学基金资助项目(10451064101006276)

摘　　要：配制了胶凝材料用量在460～550 kg/m3之间变化的自密实混凝土,采用常规方法对新拌自密实混凝土的工作性能进行了检测,采用新拌混凝土气孔结构分析仪和旋转式流变仪对自密实混凝土拌合物的气泡特征参数和筛除石子后拌合物中砂浆的流变参数进行了测试,利用混凝土绝热温升仪分析了自密实混凝土的温升过程.结果表明:胶凝材料用量在480～500kg/m3之间时,自密实混凝土的流动性、钢筋通过性和抗离析性以及气孔结构较佳,胶凝材料用量达550 kg/m3时气孔结构较差;随胶凝材料用量的增加,体系的塑性黏度和屈服应力增加,触变结构的稳定性变差,自密实混凝土的最高绝热温升和绝热温升速率峰值增大.Self-compacting concrete with a cementitious material content varying from 460 to 550 kg/m3 was pre- pared, and the workability of the concrete was tested via the normal method. Then, the air void parameters of the self-compacting concrete mixture and the rheological parameters of the mortar with gravels being filtered out were tested by using an air void analyzer and a rotary rheometer, and the temperature-rising process of the concrete was analyzed by using an adiabatic temperature-rising analyzer. The results show that the self-compacting concrete is of better tlowability, passing ability, segregation resistance as well as better pore structure when the cemenfitious ma- terial content varies from 480 to 500 kg/m3, while it is of poor pore structure when the content reaches 550 kg/m3 ; and that, with the increase of the cementitious material content, both the plastic viscosity and the yield stress of the concrete increase, the stability of thixotropic structure degrades, and the maximum adiabatic temperature rising as well as the peak of temperature rising rate increases.

关 键 词：自密实混凝土 胶凝材料 流变性能 绝热温升 

分 类 号：TU528.2[建筑科学—建筑技术科学]