摘要
采用快速冻融法,在混凝土中嵌入电阻率传感器监测冻融循环过程中混凝土的内部电阻率的演变,也测定了质量损失率以及相对动弹性模量等宏观性能的变化,并采用环境扫描电镜(ESEM)观察混凝土微观结构和形貌。试验表明:混凝土内部电阻率随冻融循环次数的增加而下降,采用电阻率衰减率能够有效表征混凝土受冻融的损伤程度;混凝土内部裂缝的不断增长造成了混凝土电阻率衰减率的上升。
With accelerated freezing and thawing tests,the electrical resistivity sensor was embedded into concrete to monitor the evolution of internal electrical resistivity subjected to freeze-thaw cycles.Besides,the mass loss rate and relative dynamic modulus of elasticity were also measured to observe the regularity of the macro-properties.And the micro-structures and interfaces between paste and coarse aggregate were observed by environmental scanning electron microscopy(ESEM).Results revealed that the electrical resistivity of concrete decreased with the increase of freeze-thaw cycle.The decay rate of resistivity could characterize the damage degree of internal concrete effectively after freeze-thaw cycles.The expansion of internal cracking caused the increase of resistivity decay rate of concrete.
作者
卢梦婷
夏锴伦
蒋林华
金鸣
LU Mengting;XIA Kailun;JIANG Linhua;JIN Ming(College of Mechanics and Materials,Hohai University,Nanjing 210098,China)
出处
《混凝土》
CAS
北大核心
2018年第12期48-52,56,共6页
Concrete
基金
国家科技支撑计划资助(2015BAB07B04)
中央高校基本科研业务费专项资金资助(2015B25814
2015B26714)
关键词
混凝土
冻融循环
电阻率
衰减率
损伤程度
concrete
freeze-thaw cycle
electrical resistivity
decay rate
damage degree
