Nanocomposite Sensing Skins for Distributed Structural Sensing

Abstract. The operational safety of civil engineered structures can be jeopardized by structural deterioration (e.g., corrosion) and damage (e.g., yielding, cracking). Structural health monitoring has been proposed to provide engineers with sensors and algorithms that can detect structural degradation in a timely manner for cost-effective correction. In this paper, a thin film material engineered at the nano-scale is proposed for distributed sensing of metallic structures. Assembled from single wall carbon nanotubes (SWNT) and polymers, the thin film’s electrical properties are designed to change in response to external stimulus such as strain or tearing. Electrical impedance tomographic (EIT) conductivity imaging is adopted to make a measurement of the film conductivity over its complete surface area. The end result is a true distributed sensor offering engineers with impressive two-dimensional maps from which strain and damage can be observed in fine detail.