Distributed Strain Monitoring Using Nanocomposite Paint Sensing Meshes

Abstract

Strain measurements are vital for monitoring the load-bearing capacity and safety of structures. A common approach is to affix strain gages onto structural surfaces. On the other hand, most aerospace, automotive, civil, and mechanical structures are painted and coated, often with many layers, prior to their deployment. There is an opportunity to design smart and multifunctional paints that can be directly pre-applied onto structural surfaces to serve as a sensing layer among their other layers of functional paints. Therefore, the objective of this study was to design a strain-sensitive paint that can be used for structural monitoring. Carbon nanotubes (CNT) were dispersed in paint by high-speed shear mixing, while paint thinner was employed for adjusting the formulation’s viscosity and nanomaterial concentration. The study started with the design and fabrication of the CNT-based paint. Then, the nanocomposite paint’s electromechanical properties and its sensitivity to applied strains were characterized. Third, the nanocomposite paint was spray-coated onto patterned substrates to form “Sensing Meshes” for distributed strain monitoring. An electrical resistance tomography (ERT) measurement strategy and algorithm were utilized for reconstructing the conductivity distribution of the Sensing Meshes, where the magnitude of conductivity (or resistivity) corresponded to the magnitude of strain, while strain directionality was determined based on the strut direction in the mesh.

Document Details

Document Type
Pub Defense Publication
Publication Date
Jan 21, 2022
Source ID
10.3390/s22030812

Entities

People

  • Kenneth J. Loh
  • Sijia Li
  • Wei-Hung Chiang
  • Yening Shu
  • Yi-jui Yeh
  • Yingjun Zhao
  • Yunan Lin

Organizations

  • United States Army Corps of Engineers

Tags

Readers

  • Materials Science and Engineering.
  • Nanocomposite Materials Science
  • Surface Coatings Technology.

Technology Areas

  • Microelectronics
  • Microelectronics - Graphene
  • Microelectronics - Microelectromechanical Systems
  • Space