Compression self-sensibility of the concrete using high content carbon black with various measurement conditions

Abstract

Self-sensing concrete (SSC) is a smart material created by dispersing a conductive filler into the concrete. This helps to increase the resistivity variation of concrete when the microstructure of the material changes under the effect of load. Thus, the stress, strain or damage of the concrete can be sensed by resistivity measurements of the concrete itself. This study aims to clarify the effects of parameters related to the measurement method on the self-sensibility of SSC. SSC specimens were prepared using carbon black with 7% volumetric content. A series of compression tests were conducted to investigate the relationship between the resistivity variation and the applied load of different test specimens in terms of excitation voltage, electrode distance and specimen size. The results show that the excitation voltage need to be large enough to generate a current of suitable stability when measuring the self-sensibility of SSC. The resistivity of all specimens decreased with increasing compressive load on the SSC specimen. The larger the specimen size and the smaller the electrode distance, the more pronounced the resistivity variation.