Experimental Study on Thawing Process of Frozen Soil Based on CT Scanning
X. F. Kang†, H. Zhang†*, & V. Martins‡
†College of Mechanical and Transportation Engineering, China University of Petroleum-Beijing, Beijing, 102249, China,
‡Laboratório de Palinofácies e Fácies Orgânica, Departamento de Geologia, Universidade Federal do Rio de Janeiro, UFRJ, Rio de Janeiro, RJ 20559, Brazil
ABSTRACT: In order to explore the feature of frozen soil thawing based on CT scanning, the experiment is carried out under the indoor temperature of 20℃. The sample of frozen soil which is -27℃ is taken into isothermal air to melt by natural convection. And the CT images are obtained by X-ray scan, and at the same time, its temperature-time history is recorded. The curve of grayscale-time is acquired by counted CT images at each moment, and compared with its temperature time history. The results show that the average grayscale increases obviously with temperature rising and thawing in frozen soil. However after sample thaws completely, the average grayscale is not practically changing even temperature still rising. A break point is obviously observed in the graph of grayscale-time at the moment of phase-transition finished, which is considered as a symbol of the completion of frozen soil melting.
Keywords : Frozen soil; X-CT; Average grayscale; Thawing.
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