Nano-carbon black and carbon fiber as conductive materials for the diagnosing of the damage of concrete beam

Abstract

Author's personal copyThe nano-carbon black (NCB) and carbon fiber (CF) as electric conductive materials were added into the concrete. The effect of the NCB and CF on the mechanical properties and on the fractional change in resistance (FCR) of concrete was investigated. The relationships among the FCR, the strain of initial geometrical neutral axis (IGNA) and the beam damage degree were developed. The results showed that the relationship between the FCR and IGNA strain can be described by the First Order Exponential Decay function, and the internal damage of concrete beam was reflected by the relationship between damage degree and resistance.The authors acknowledge the National Natural Science Foundation of China (Grant: 50278013), the National Natural Science Foundation of China (Grant: 51121005), State Key Laboratory of Coastal and Offshore Engineering, DUT and Fundacao para a Ciencia e a Tecnologia (SFRH/BPD/22680/2005), the FEDER Funds through "Programa Operacional Factores de Competitividade - COMPETE" and by Portuguese Funds through FCT - within the Projects PEst-CMAT/UI0013/2011 and PTDC/MAT/112273/2009