Electrical–structural characterisation of smart carbon-based textile reinforced concrete beams by integrative gauge factors

The goal of this study is to characterise the piezoresistive capabilities of self-sensory carbon roving reinforcements by means of integrative gauge factors (GFs). The correlation between the measured integrative electrical resistance of the carbon rovings and the distributed strain is experimentally investigated by two different textile reinforced concrete beams under monotonic flexural loading. Because the microstructural mechanism of the rovings within the concrete matrix affects the electrical resistance, the GF is a function of the structural health. Two approaches to explore the GF are suggested: the first is by considering the design and damaged states separately and accordingly defining a constant GF for each state, and the second is by considering the entire structural response which leads to a continuous non-linear correlation. The potential of the two representations of GFs is presented by investigating the two beams. It is demonstrated that similar ranges of GFs are obtained for both beams, which further demonstrates the potential of using the proposed methodology for quantitative monitoring purposes.