Study of Carbon Nano-Fiber Aggregates with AC Measurements
Past studies have demonstrated the use of self-consolidating carbon nanofiber concrete (SCCNFC) as a structural sensor which led to the development of carbon nanofiber aggregates (CNFAs). Many researchers have adopted the four probe technique to measure DC electrical resistance variation of concrete composites like CNFAs to study the effect of stimuli on structures. In this research, four probe CNFAs were modified into two-probe, and its response in circuits with DC and AC (20Hz to 300kHz) inputs for loaded and non-loaded states were compared. The study was further extended with the optimization of AC frequency and carbon nanofiber (CNF) content to achieve a maximum and reliable response from CNFAs in response to various stimuli. The optimized CNFAs were then tested to develop waterproof CNFAs with the outer coating. The study finally gave the optimized waterproof CNFA to be used in an AC circuit of optimized frequency that can be implemented in reliable and consistent real-time structural health monitoring.