关键词: 纳米碳黑;压阻效应;灵敏度;含水量

Abstract: Effect of various moisture content on properties of piezoresistivity of cement-based composites with nano carbon black were studied by drying materials. The results show that composites present two states of piezoelectricity properties when moisture content changes,that is,piezoelectricity properties will be positive under condition of high moisture content or very desiccation,and will be negative under a proper content of moisture. The curves of△R/R0-stress due to loading and unloading don't coincide each other,and it shows hysteretic characteristics and obvious nonlinear property. In addition,the sensitivity of piezoelectricity reduces with increase of stress and the composites show insensitive under high stress.

Key words: nano carbon black;piezoresistance effect;sensitivity;moisture content