摘要
为了解决大体积混凝土内部温度应力和裂缝问题,采用PVP分散剂、磁力搅拌和超声分散等方法制备碳纳米管水泥基材料。观察不同碳纳米管掺量水泥基材料在16~600℃热膨胀系数的变化,从微观尺度进行机理分析,并通过力学性能进行验证。结果表明,不同碳纳米管掺量时热膨胀系数变化趋势相似,掺量为0.3%时,材料在正向、负向的热膨胀系数始终在其它掺量之下,体积膨胀最小,收缩最大。这说明碳纳米管掺量为0.3%时,水化反应充分,密实度显著提升,使其内部裂缝减少,温度应力减弱,宏观上表现为抗压、抗折强度最高。
In order to solve the internal temperature stress and crack problem of mass concrete,carbon nanotube cement-based materials were prepared by PVP dispersant,magnetic stirring and ultrasonic dispersion method.Observe the change of thermal expansion coefficient at 16~600℃for different proportions of carbon nanotube cement base.The pore size distribution map and scanning electron micrograph were used to analyze the mechanism from the microscopic scale and verified by mechanical properties.The results show that the trend of each proportion is similar,but when the dosage is 0.3%of cement,the coefficient of thermal expansion in the positive and negative directions is always under other dosages,the volume expansion is the smallest,and the shrinkage is the largest.This indicates that the hydration reaction is sufficient when the dosage is 0.3%,and the compactness is remarkably improved,so that the internal cracks are reduced and the temperature stress is weakened,and macroscopic exhibition is the highest in the compressive and flexural strength.
作者
张淑文
张杰
王贵春
ZHANG Shuwen;ZHANG Jie;WANG Guichun(School of Civil Engineering,Zhengzhou University,Zhengzhou 450001,China)
出处
《新型建筑材料》
北大核心
2019年第5期41-45,共5页
New Building Materials
基金
中国博士后科学基金项目(2017M612419)
河南省重点科研项目(17A580004)
关键词
碳纳米管
水泥基材料
微观结构
热膨胀系数
力学性能
carbon nanotubes
cement-based materials
microstructure
thermal expansion coefficient
mechanical properties
