THERMAL DESIGN IN PERMAFROST SOILS

• Main Authors: H. R. Peyton, Ts Surface Tempera Ture
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Soi; permafrost
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.585.5232; http://pubs.aina.ucalgary.ca/cpc/CPC3-85.pdf

Other papers presented a t the Thi rd Canadian Conference on P e r m a f r o s t have clear ly outlined the extent of permafros t and a grea t many of the problems associated with operations in permafros t regions. I t has also been c lear ly shown that the permafros t environment is one in which grea t forces a r e a t work and that these fo rces a r e in delicate balance. Small man-made dis turbances can then be expected to t r igger grea t undesirable changes unless c a r e is exercised i n maintaining the balance. One method of maintaining the appropriate balance is to design facil i t ies with the thermal reg ime predetermined and with the soi l to be retained i n the frozen s tate o r purposefully melted a t a predetermined ra t e and to a predetermined extent. The object of this paper is to d iscuss the methods of calculating the thermal regime, and a se t of examples a r e used to i l lus t ra te some design processes. THE NATURAL THERMAL REGIME I t has been shown by R. J. E. Brown that the seasonal surface tempera ture variation causes an annual tempera ture oscillation below the surface which dec reases in amplitude with depth. The envelope sur-rounding a l l of the tempera tures occurr ing through a year is called a "trumpet curve " and is schematical ly shown i n F igure 1 with the geo-the rma l gradient superimposed. General fea tures on Figure 1 a r e interest ing.- The mean annual soil surface tempera ture is the extrapolation of the geothermal gradient to the ground surface.- The su r face tempera ture fluctuation can generally be a s sumed to f i t the equation Ts = MASST + A s in (wt-a) where