DETERMINATION OF THE UNFROZEN WATER CONTENT OF SALINE PERMAFROST USING TIME-DOMAIN REF'LECTOMETRY (TDR)

• Main Authors: E. Hivonl, D. C. Segw, Graduate Stlidenr
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: permafrost
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.564.3033; http://pubs.aina.ucalgary.ca/cpc/cpc5-257.pdf

Tie-Domain Reflectomeq V R) was used to carry out measurement of the unfrozen water content on two soils at three salinities over the temperature range-1 to-12OC. It was observed that as the amount of d o z e n water content increased at high salinity (i.e. 30 ppt) the location of the open circuit response on the TDR trace was obscured due to signal attenuation. A comparison,was established between the predicted d o z e n water content using the NaCl phase diagram and the measured values for the clean sand (sol A). An, evaluation of the unfrozen water content for the silty sand (soil B) using data from Hutchinion (1989) based on a method proposed by Banin and Anderson (1974) and modified by Patterson and Smith (1983) did not correlate well with the experimental measurement on the low plastic soil. In conclusion. the use of short parallel transmission lines to evaluate the unfrozen water content with TDR is a simple and reliable technique to determine the d o z e n water content. La technique TDR (timedomain-reflectomew) a 6t6 utilisde pour mesurer la teneur en eau non gel& dam deux types de sols gel6 B trois saliit6s diffhentes dam I'intervalle de temflature de-1 OC ii-12OC. Une atthation du signal. causant une impr6cision de la ddtermination du circuit ouvert sur la trace du TDR, est observ6e lorsque la quantit6 d'eau non gel6e augmente due i une haute salinit6. Les r6sultats exp6rimentaux pour le sable uniforme (sol A) ont 6t6 compar6s ii la teneur en eau non gel & p6dite par le diagramme de phase du NaCI. Une Caluation de la teneur en eau non gel6e pour le sable silteux (sol B) dtablie B partir de donn6es prQent&s par Hutchinson (1989) bas & sur une m6thode de Banin et Anderson (1974) et modifide par Patterson et Smith (1983) ne correspond pas favorablement aux r6sultats exp6rimentaux pour ce sol de faible plasticit6. En conclusion, l'utilisation de lignes de transmission parallMles courtes avec la technique du TDR permet une dvaluation simple et fiable de la teneur en eau non gel6e darts les ...