Annual variation of the Frost Table at Kangerlussuaq airport

Abstract

Anglès: Permafrost has become the most important feature in civil engineering in all the arctic regions. The construction of a new structure, such and road or and airfield, changes the thermal regime of the ground leading to a faster degradation of the frost table. The heat caused by the new structure speeds the thawing process of permafrost giving place to differential settlements on the surface and longitudinal cracks along the edges of roads and highways.

One of the techniques to mitigate those effects is the use of reflective surfaces. It has been probed that a lighter color reflects more sunlight avoiding the rise of temperatures that makes permafrost to thaw prematurely.

The purpose of this Thesis has been carrying out Ground Penetrating Radar investigations in different test areas of Kangerlussuaq airport in order to evaluate the changes that the frost table is experiencing underneath a white painted surface and black asphalt.

The results obtained have shown that if the paint is maintained in good conditions the thickness of the active layer is considerably reduced under zones with reflective surfaces. Furthermore, the data obtained from the fieldwork has been compared with a thermal model which predicts the depth of the frost table from a deemed period of time. Both analyses have led to similar results, fact that should promote the development of light-colored asphalt materials. Future studies should focus in the improvement of the hitches that those kind of paints present, like the low skid resistance and their high maintenance cost.