Self-sensing composites with damage mapping using 3D carbon fibre grid

Self-sensing composites are becoming a technological breakthrough in structural health monitoring of aircraft structures and wind turbine blades. In this study, sandwich-structured composites are developed with intersecting and non-intersecting 3D carbon fibre grids. Damage sensing of the first type is based on the integrity of fibre-to-fibre contacts. The second type is based on the carbon nanotube-modified glass fibre plies, working as a conducting layer for the non-intersecting carbon fibre grid. The experimental section consists of indentation, impact and delamination tests. The damage area and size are determined from the local electrical resistance deviation. Sensitivity results are compared between samples with 0.1–0.5 wt% carbon nanotube concentrations. Additionally, the method is supported by numerical analysis of electric potential gradient using finite element modelling. This innovative approach demonstrates the feasibility of using self-sensing composites for potential remote SHM applications. While further work is required to validate the method's accuracy and effectiveness under real-world conditions, the results highlight its potential to identify core indentation, puncture damage, and interlaminar delamination without external sensors, offering significant safety and maintenance planning advancements.