Study on the performance of graphene-enhanced cementitious piezoresistive sensors in self-sensing concrete members

Abstract

Cementitious composites incorporating conductive fillers exhibit piezoresistive properties, where their electrical resistance changes in response to applied stress. This characteristic makes them ideal for use in cement-based sensors. In this study, graphene nanoplatelets (GNPs) were utilized as conductive fillers to fabricate graphene-enhanced cementitious composite sensors (GCBS), and their piezoresistive behavior was thoroughly investigated. Self-sensing concrete members were casted by embedding GCBS into concrete beams and columns. The self-sensing capability of these members, including stress variation detection, damage progression monitoring, and vibration property assessment, were evaluated through both static and dynamic testing. Static tests revealed that the GCBS effectively responded to applied loads, with resistance decreasing consistently as stress increased.Furthermore, the GCBS demonstrated the ability to detect the progression of internal cracks within the concrete members. Dynamic tests indicated that the GCBS could identify the frequencies of the concrete members, exhibiting hightened sensitivity to high-frequency vibrations. However, polarization effects introduced significant low-frequency noise, which reduced the accuracy of the GCBS, particularly for low-frequency signals. This study highlights the potential of cement-based piezoresistive sensors as a promising solution for advancing self-sensing technology in concrete structures.