ISSN: 1546-962X
Published Online: 3 January 2005
Page Count: 16

Density Compensation of TDR Calibration for Geotechnical Applications

Yu, X
Post Doctoral Researcher, School of Civil Engineering, Purdue University, West Lafayette,IN

Drnevich, VP
Professor, School of Civil Engineering, Purdue University, West Lafayette,IN

(Received 9 September 2003; accepted 30 July 2004)

Abstract

Time Domain Reflectometry (TDR) technology has been widely used in areas such as agricultural science, soil science, and water resources for measuring soil volumetric water content and is beginning to be used in geotechnical engineering. Calibration relationships, which generally relate the soil volumetric water content to TDR measured dielectric constant, are critical for the accuracy of TDR measurements. For TDR technology to be useful for geotechnical engineering practice, the calibration relationship needs to be expressed in terms of gravimetric water content. Besides, geotechnical engineering deals with more compacted earth materials, where the effects of soil density on TDR calibration are significant. This paper introduces an improved TDR calibration relation that accounts for the density of soil skeleton while at the same time is simple in format. Application of this calibration relationship shows that it significantly reduces data scatter and achieves more accurate results than other existing calibration relationships.

Keywords:
Time Domain Reflectometry (TDR), water content, density, TDR calibration, geotechnical engineering

Paper ID: JAI12190
DOI: 10.1520/JAI12190
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