Polystyrene-MWCNT Based Nanocomposite Multifunctional Strain Sensor: Dynamic Monitoring of Civil Engineering Structures

Structural sensing and dynamic monitoring of critical infrastructure is essential to maintain the ageing critical infrastructure of US. To this end various sensing mechanisms and innovations have been used in the recent past such as strain sensors, accelerometers etc. Measurement of strain gives first hand information about the state of stresses in a structure. The effectiveness of multiwalled carbon nanotube (MWCNT) films as strain sensors has been demonstrated by the authors (Vemuru et al. 2009) and other researchers. In this paper the real time dynamic response of MWCNT polystyrene nanocomposite thin film sensors is studied and experimental results presented of both its dynamic response as well as its response to temperature. Experimental results demonstrate a linear response from the MWCNT nanocomposite. Further electromechanical properties observed are completely reversible and stable. The temperature response of the nanocomposite film is also studied experimentally and results presented. It is demonstrated that the nanocomposite thin films monitors the strain very effectively and can be used as a multifunctional material in civil, mechanical and aerospace applications.