Laser Characterization of Fine Aggregate

This report describes the results of a research effort to establish the feasibility of using a laser monitoring system to provide real-time data to characterize aggregate properties in a laboratory or field environment. This was accomplished by using the known physical, chemical and mechanical properties and aggregate criteria as defined by AASHTO and ASTM test methods and correlating these properties with spectral emission data induced by a laser in a process referred to as Laser Induced Breakdown Spectroscopy (LIBS). The authors believe that the success of this research in making such a correlation is based on two primary factors: 1) the laser ablation process can generate an emission with over 13,000 potential wavelengths, and these data provide a rich spectra that can be used to pattern match or fingerprint latent properties within the material that are not readily identifiable by conventional elemental or mineralogical testing methods; and 2) the development of multivariate statistical software models that can process large spectral arrays has made it possible to manage and analyze in real time data from the emission spectra generated during a laser ablation process. The primary advantage of LIBS over conventional aggregate testing and screening methods is its potential to identify the aggregate source in real time in the field without sample preparation. This provides a means to identify preapproved materials and to ensure that only such materials are being introduced into the production process. It also provides a means to calibrate the spectral pattern or fingerprint against known engineering properties to determine whether the aggregate can be expected to pass or fail designated test criteria. A pooled fund study is currently under development to demonstrate the subject technology in the field, providing owner/agencies with a real-time, recording tool for monitoring materials used in highway construction.

• Record URL:
  http://www.oktc.org/otc/files/finalReports/OTCREOS10.1-12-F.pdf
• 
• Supplemental Notes:
  • This research was sponsored by the U.S. Department of Transportation, University Transportation Centers Program.
• Corporate Authors:

  Oklahoma State University, Stillwater

  School of Civil and Environmental Engineering
  207 Engineering South
  Stillwater, OK  United States  74078-5033

  Oklahoma Transportation Center

  2601 Liberty Parkway, Suite 110
  Midwest City, OK  United States  73110

  Research and Innovative Technology Administration

  1200 New Jersey Avenue, SE
  Washington, DC  United States  20590
• Authors:
  • Chesner, Warren H
  • McMillan, Nancy J
  • Cross, Stephen A
• Publication Date: 2012-12

Language

• English

Media Info

• Media Type: Digital/other
• Edition: Final Report
• Features: Figures; Photos; References; Tables;
• Pagination: 59p

Subject/Index Terms

• TRT Terms: Aggregates; Construction; Field tests; Lasers; Monitoring; Properties of materials; Real time data processing; Spectroscopy
• Uncontrolled Terms: Laser induced breakdown spectroscopy
• Subject Areas: Construction; Highways; Materials; I36: Aggregates; I50: Construction and Supervision of Construction;

Filing Info

• Accession Number: 01494504
• Record Type: Publication
• Report/Paper Numbers: OTCREOS10.1-12-F
• Contract Numbers: DTRT06-G-0016 (Grant)
• Files: UTC, TRIS, RITA, ATRI, USDOT
• Created Date: Sep 26 2013 1:29PM