Carbon Nanotubes Doped Cement-Based Sensors for Dynamic Response Measurements

Infrastructure is facing many environmental and manmade challenges. Structural health monitoring is of great need in such scenarios. It incorporates many conventional sensors like electric strain gauge (ESG), optical fibers wire, and piezo ceramic materials i.e., Lead zirconate titanate (PZT), but accompanied by compatibility and durability issues. This paper shows the suitability of cement-based sensors (50 mm × 50 mm × 50 mm) for concrete structures in embedded form, made by doping multi-walled carbon nanotubes (MWCNTs) in cement. This work shows the experimental studies on these sensors for dynamic response measurement against the application of sinusoidal compression waves generated through an LDS electrodynamic shaker in a laboratory environment keeping the frequency range 7–25 Hz covering the typical frequency content of the dynamic response of large civil engineering structures. Natural frequency values thus obtained from time history responses of MWCNT sensors and PZT patch have a good agreement. The results of vibration tests show that these sensors give suitable responses and retain all dynamic features of the input thus providing useful information for structural health monitoring (SHM). Hence paved the way for the application of such sensors having higher compatibility and durability for smart civil engineering structures.