Carbon-based textile as a smart sensory device for self-monitoring of fiber-reinforced concrete elements

This study investigates a novel self-sensing approach for monitoring the structural health of concrete structures by developing hybrid textile-fiber-reinforced concrete (TFRC) elements. The proposed concept offers to use carbon-based textile positioned within electrically conductive concrete medium, functioning both as the primary reinforcement system and as a sensory device for the concrete body. By exploring changes in the impedance spectrum and characterizing the equivalent electrical circuit, measurements of the electrical resistance ( R ) and capacitance ( C ) of the concrete are achieved. Both electrical properties are used as indicators for assessing the structural health by two transverse gauge-factors, namely G F R ⊥ and G F C ⊥ . To enhance the electrical conductivity of the concrete body, additive short carbon fibers (CFs) are used, which also enhance the mechanical properties of the element. It is demonstrated that CFs significantly affect the electrical resistivity and permittivity of the concrete. It is observed that the percolation threshold is at a volume fraction of V f = 0.6%, and the highest electrical permittivity is at V f = 1.2%. Results showed that the smart hybrid TFRC elements exhibited consistent, repetitive, and sensitive electrical responses associated with straining and cracking of the concrete matrix.