EVALUATION OF AGWA-II THERMAL CONDUCTIVITY SENSORS FOR SOIL SUCTION MEASUREMENT

Several tests (both laboratory and full-scale) were conducted to assess the potential of AGWA-II thermal conductivity sensors to measure soil suction in geotechnical engineering applications. The tests conducted in the laboratory included examining the response of the sensors submerged in water, calibrating the sensors in a pressure plate, and measuring soil suction in undisturbed soil specimens. Initial tests conducted on the sensors indicated some inaccuracies associated with the linear calibration curves suggested by the manufacturer. The calibration results showed that the calibration curves for the sensors were bilinear with a breaking point at about 175 kPa. Reasonable agreement was found between the calibration curves obtained in this study and those provided by the manufacturer for matric suction ranging from 0 to 175 kPa. However, large deviations in the calibration curves were observed at suction above 175 kPa. With the calibrated sensors, a testing program was carried out by measuring soil suction in undisturbed soil specimens. Upon the completion of the laboratory tests, the sensors were installed in the subgrade soils of an indoor test track for long-term monitoring. The sensor outputs were found to be relatively consistent and stable with time.

• Record URL:
  • http://onlinepubs.trb.org/Onlinepubs/trr/1989/1219/1219-013.pdf
• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/isbn/030904815X
• Supplemental Notes:
  • This paper appears in Transportation Research Record No. 1219, Geotechnical Engineering 1989. Distribution, posting, or copying of this PDF is strictly prohibited without written permission of the Transportation Research Board of the National Academy of Sciences. Unless otherwise indicated, all materials in this PDF are copyrighted by the National Academy of Sciences. Copyright © National Academy of Sciences. All rights reserved
• Authors:
  • Wong, DKH
  • FREDLUND, D G
  • Imre, E
  • Putz, G
• Publication Date: 1989

Media Info

• Features: Figures; References; Tables;
• Pagination: p. 131-143
• Monograph Title: Geotechnical engineering 1989
• Serial:
  • Transportation Research Record
  • Issue Number: 1219
  • Publisher: Transportation Research Board
  • ISSN: 0361-1981

Subject/Index Terms

• TRT Terms: Accuracy; Calibration; Laboratory tests; Measurement; Monitoring; Sensors; Soil suction; Subgrade (Pavements); Test tracks; Thermal conductivity; Time duration
• Uncontrolled Terms: Long term
• Subject Areas: Geotechnology; Highways; I42: Soil Mechanics;

Filing Info

• Accession Number: 00494773
• Record Type: Publication
• ISBN: 030904815X
• Files: TRIS, TRB
• Created Date: Jun 30 1990 12:00AM