Real-time structural health monitoring of carbon fiber-reinforced plastic sandwich structures with carbon nanotube-dispersed core using electromechanical behavior data

Abstract

Sandwich composite structures have been widely used in many industrial fields because of their high bending strength, especially in large structures. As such, the need for structural health monitoring of sandwich structures to reduce maintenance costs during their lifetime is highly sought after. Here, the structural health status of sandwich composite structures comprising carbon nanotube (CNT)-dispersed cores and carbon fiber-reinforced polymers (CFRPs) was monitored in real time using self-sensing data. Previous studies using self-sensing methods have only monitored the occurrence of damage and deformation in the elastic region. Here, we conjointly investigated various failure mechanisms in real time to propose a self-sensing health index system to determine the damage severity in sandwich structures. The self-sensing technique allows for the analysis of various damage types in both the skin and core of sandwich structures. Furthermore, the actual propagation of damage (i.e., the length of the core crack) in composite sandwich structures can be investigated. The results demonstrate that self-sensing structural health monitoring is an effective and reliable method for analyzing sandwich structures, with promising applications in aircraft components, wind turbines, and personal aerial vehicles.