Development of an Optical Displacement Transducer for Routine Testing of Asphalt Concrete

Routine mechanical characterization of asphalt concrete is performed under small-strain levels with on-specimen linear variable displacement transducers (LVDTs) as deformation measuring devices. An optical LVDT was conceptually proposed and evaluated in this study to serve as a viable noncontact alternative to physical LVDTs. The envisioned device consists of a pair of low-end low-resolution grayscale cameras, each monitoring a virtual gauge point, i.e., a small untreated surface area of the tested specimen. The gauge length is the distance between the two virtual gauge points, and the sought-after information is their differential in-plane translation. Digital image correlation techniques were employed for the measurement, operated on the natural material texture without requiring speckle coating. As a first step toward evaluating the concept, the study explored both the precision and the accuracy that may be achieved with one low-resolution image sensor. A calibration scheme was also offered for introducing object-scale dimensions into the analysis. From this predevelopment study it is concluded that the envisioned optical LVDT is viable, rendering the idea worthy of consideration.

• Record URL:
  https://doi.org/10.1061/(ASCE)MT.1943-5533.0001570
• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/issn/08991561
• Supplemental Notes:
  • © 2016 American Society of Civil Engineers.
• Authors:
  • Hamam, Tomer
  • Levenberg, Eyal
  • Zelnik-Manor, Lihi
• Publication Date: 2016-9

Language

• English

Media Info

• Media Type: Web
• Features: References;
• Pagination: 04016066
• Serial:
  • Journal of Materials in Civil Engineering
  • Volume: 28
  • Issue Number: 9
  • Publisher: American Society of Civil Engineers
  • ISSN: 0899-1561
  • EISSN: 1943-5533
  • Serial URL: http://ascelibrary.org/journal/jmcee7

Subject/Index Terms

• TRT Terms: Asphalt concrete; Coatings; Deformation; Measuring instruments; Sensors; Transducers
• Uncontrolled Terms: Digital image correlation; Linear variable differential transducers
• Subject Areas: Highways; Materials; Pavements;

Filing Info

• Accession Number: 01598272
• Record Type: Publication
• Files: TRIS, ASCE
• Created Date: May 2 2016 10:15AM