Effect of matrix electrical and micro-structural properties on the self-sensory capabilities of smart textile reinforced composites

This study investigates the effect of the matrix properties on the structural and sensory capabilities of smart self-sensory textile reinforced cement composites, in which carbon rovings are simultaneously used as the main reinforcement system and as the sensory agent. The investigation focuses on two different cementitious matrices: Portland cement (PC) and Magnesium Phosphate cement (MPC). The differences are associated with the matrix electrical and micro-structural behaviors. It is demonstrated that compared to PC matrix, MPC matrix is characterized by a relatively high electrical resistivity, which enhances the electrical signal. It is further demonstrated that the advanced material properties of the MPC matrix improves the textile-matrix interaction, and, as a result, the structural performance of the composites. The characterization is affected and reflected by the measured electrical resistance change (ERC). The integrative gauge factor (GF) concept was chosen to demonstrate the different structural – electrical correlations associated to the matrices. It is presented that the matrix type is reflected by the value and trend of the GF. While carbon-based textile reinforced PC elements are characterized by nonlinear and lower GF values, in the case of textile reinforced MPC elements, the GF is linear and its value is about 2.5 times higher.