摘要
利用珊瑚砂取代天然河砂进行混凝土的配合比设计,系统研究了珊瑚砂混凝土的抗折强度、抗压强度、劈裂抗拉强度、干燥收缩以及早期抗开裂性能,同时用相同配合比参数的河砂混凝土进行对比。此外,还对珊瑚砂混凝土的抗氯离子渗透性、抗碳化性等耐久性以及水化产物的微观结构进行了分析。试验结果表明,珊瑚砂混凝土的抗压强度要低于河砂混凝土,而抗折强度、劈裂抗拉强度则相差不大;珊瑚砂混凝土的干燥收缩性能、早期抗开裂性能、抗氯离子渗透性以及抗碳化性均要好于河砂混凝土。珊瑚砂混凝土和河砂混凝土的28d水化产物基本相同,都含有Ca(OH)_2,钙矾石AFt,CaCO_3和C-S-H凝胶。珊瑚砂由于其凸凹多孔,使得其界面过渡区的黏结力要大于河砂混凝土,这极大改善了其界面的结构性能。
The coral sand instead of natural fiver sand for concrete mixture ratio design is used in this paper. Com- pared with the same mixing ratio parameters of river sand concrete, the compressive strength, flexural strength, splitting strength, shrinkage and crack resistance performance of coral sand concrete are systematically reseached. In addition, the chloride ion permeability, carbonation resistance and microstrncture of coral sand concrete are also analyzed. The test re- sults show that the coral sand concrete compressive strength is lower than river sand concrete, flexural strength and split- ting strength is the same. The shrinkage, crack resistance performance, chloride ion permeability and carbonation resis- tance are better than coral sand concrete. The hydration products of 28 days coral sand and river sand concrete are basi- cally the same, both contain Ca（OH）2, AFt, CaCO3 and C-S-H. The internal porous microstrncture of coral aggregate makes the interface bond strength between coral aggregate-cement paste bigger than ordinary aggregate-cement paste, which can improve the interface structure performance greatly.
出处
《混凝土与水泥制品》
2016年第7期16-21,共6页
China Concrete and Cement Products
关键词
珊瑚砂
力学性能
耐久性能
微观结构
Coral sand
Mechanical properties
Durable performance
Microstructure
