Comparison Between Grid Points and Grid Lines For Detecting, Locating and Quantifying Damage in Large Polymer Composite Structures Made of Electrically Non-Conductive Fibers and Carbon Nanotube Networks

摘要

This paper presents a novel and practical structural health monitoring (SHM)rntechnique for detecting, locating and quantifying damage in large polymerrncomposite structures made of electrically non-conductive fibers and carbonrnnanotube networks using electrical resistance measurement (ERM). Largerncomposite plates were prepared by adding multiwalled carbon nanotubesrn(MWCNTs) into epoxy and then dispersing the modified epoxy in glass fibers. Thernplates were mounted with a grid of electrical contacts made from silver-epoxyrnpaints. Two different types of electrical contact geometry were examined for ERM.rnOne was grid points and the other was grid lines. Drilled holes of different sizesrnwere created in the plates mounted with grid points and grid lines. The electricalrnresistance measurements were made before and after drilled holes. It was found thatrndrilled holes were detected, located and quantified in the large plates based on thernsignificant increases in electrical resistance. The significant increases measuredrnusing grid points were more pronounced in comparison to that measured using gridrnlines. The experimental results demonstrate that grid points provides much betterrndamage detection, location and quantification compared to grid lines, in addition tornhigher increase in electrical resistance.