A tentative proposal of snow tunnel construction procedure for a subsurface observation station in the Antarctica

Abstract

Most observation stations on the ice sheet in the Antarctic are constructed as subsurface structures. These subsurface stations are composed of buildings and facilities in the snow shelter having a large strength against snow. Mizuho Station of the Japanese Antarctic Research Expedition is a remarkable example of the small subsurface station in the ice sheet. Buildings and facilities of the observation station are constructed in the snow tunnel with little reinforcements. Since hard work is required to construct a snow tunnel for this type of observation station, an efficient method of snow tunnel construction is examined in this paper. The method proposed in this paper consists of the following procedures : (1) Net-fences are set up around the construction site. (2) The huts are constructed. (3) Snow is controlled to be deposited along the net-fences. (4) The snow deposit will grow thicker along the net-fences. (5) Finally a snow tunnel enveloping the net-fences and the huts will be formed. In order to realize the snowdrift control procedure, preliminary tests on the ability of net-fences to prevent wind and to deposit snow are examined in this paper. It is found that the ability of the net-fences can be explained by the variable φ, which is the density ratio of the net. It will be possible to use the net-fences for the snowdrift control under the condition that the combination of the density ratio of the net and the thickness of the yarn is devised effectively