摘要
利用珊瑚砂取代天然河砂进行了混凝土的配合比设计,系统研究了水胶比、砂率和胶凝材料用量三个因素对珊瑚砂混凝土性能的影响,并通过XRD、SEM和TG-DSC等测试手段对珊瑚砂混凝土和河砂混凝土的微观结构进行了对比分析。试验结果表明,珊瑚砂混凝土的抗压强度随着水胶比的增大而减小,随着砂率的增大先减小后增大,随着胶凝材料用量的增加先增大后减小,在胶材用量为420 kg/m^3时,抗压强度达到最大值;珊瑚砂混凝土和河砂混凝土的28 d水化产物基本相同,都含有氢氧化钙Ca(OH)_2,钙矾石AFt,碳酸钙CaCO_3和C-S-H凝胶。珊瑚骨料内部多孔的微观结构使得珊瑚骨料-水泥浆体的界面黏结力较普通骨料-水泥浆体的界面黏结力大,大大改善了界面结构性能。
We use coral sand instead of natural river sand for concrete mixture ratio design,and study the impact of water-cement ratio, sand ratio, and cementitious material content on coral sand concrete properties. Besides, we analyse the microstructure of the coral sand concrete and natural river sand concrete through the test means such as XRD, SEM and TCJ-DSC. The test results show that the coral sand concrete compressive strength decreases with the increasing of water cement ratio, the coral sand concrete compressive strength first decreases then increasing with the increasing of sand ratio, the coral sand concrete compressive strength first increases then decreases with the increasing of dosage of cementitious material, the compressive strength achieves maximum when the dosage of cementitious material is 420 kg/m^3. The hydration products of 28 d coral sand and river sand concrete are basically the same, both contain Ca （OH）2, AFt, CaCO3 and C-S-H. The internal porous microstructure of coral aggregate makes the interface bond strength between coral aggregate-cement paste bigger than ordinary aggregate-cement paste, improves the interface structure performance greatly.
出处
《建材世界》
2016年第2期15-20,共6页
The World of Building Materials
关键词
珊瑚砂
配合比设计
水胶比
砂率
微观结构
coral sand
mixture ratio design
water-cement ratio
sand ratio
microstructure
