摘要
碾压混凝土中掺用氧化镁将产生延迟性膨胀,可补偿混凝土温降过程中的体积收缩,有助于温控防裂。但在筑坝工程中,碾压混凝土使用的氧化镁种类众多,掺入水泥后的适应性有待研究。通过选取两个厂家、三种型号、三种不同掺量下的氧化镁膨胀剂,掺入水泥进行凝结时间、安定性及7d、28d抗压强度和抗折强度和水养7d、水养28d及干养21d限制膨胀率等物理性能试验,得出结果表明,其物理性能呈现一定的规律性,进而通过分析其原因,验证出氧化镁膨胀剂的一些基本特性。
When mixed into the roller compacted concrete（RCC）, light-burned Magnesia can cause delayed expansion, which can compensate the volume shrink when the temperature drops so as to control the temperature and prevent the crack. Currently, in the dam engineering, different MgO expansive agents are used in the RCC, while their adaptability when mixed into the cement is still in need of further analysis. In the article, a series of conventional physical indices, such as the time setting of cement, cement stability, compressive and flexural strength of cement mortar （7d and 28d）, restrained expansion rate of cement mortar （7d maintained in the water and 21d maintained in the air） are experimented to analyze the adaptability of Magnesia expansive agents of 3 types and 3 volumes. The research results show that the manufacturers, types and volumes of Magnesia expansive agents have a close relationship with the physical performances. Further, the causes are analyzed and the basic characteristics of MgO expansive agents are tested and verified.
作者
蔡杰龙
杨永民
王梓鑫
蔡灿旭
CAI Jie-long;YANG Yong-min;WANG Zi-xin;CAI Can-xu(Guangdong Research Institute of Water Resources and Hydropower,Guangzhou 510635,China;Guangdong New Material and Structural Engineering Technology Research Center,Guangzhou 510635,China;Guangdong Provincial Key Sciemific Research Base,Guangzhou 510635,China;South China University of Technology,Guangzhou 510640,China)
出处
《广东水利电力职业技术学院学报》
2018年第3期13-17,共5页
Journal of Guangdong Polytechnic of Water Resources and Electric Engineering
基金
广东省水利科技创新项目(2016-23)
关键词
氧化镁膨胀剂
物理性能
规律性
magnesia expansive agent
physical performance
regularity
