A new generation rammsonde has been developed recently for detection of snowpack property. It measures the reflectivity of red light, the penetration force on a cone 'and the electrical conductivity around the cone simultaneously in a few minutes. Field studies have proved that the new instrument enables detection of weak snow layers, tracing snow layer structures and classification of snowpacks for avalanche forecasts. However, the instrument is incapable of detecting very thin weak layers which were detected by the shovel shear test but cannot be seen by the naked eye.

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To enable a comparative study of the snow-fighting measures in each municipality in Aomori Prefecture, Japan on the basis of snow-removal budget (yen), the depth of snowfall(cm), length of road to be cleared of snow(m), and the number of households, the term Snow Management Unit (yen·cm^-1·(m/household)^-1) is proposed. The Snow Management Unit shows the (exclusively mechanical) snow-removal expense versus snowfall unit (cm) and vital road-length unit(m) (excluding trunk roads such as national or prefectural highways) per household. In urban areas with many multistory housing complexes, snow-removal budgets are larger while the road length between households is shorter. Therefore, the amount spent per road-length unit increases, which means the Snow Management Unit goes up. In remote rural areas the scale of budget is small while the road length between households is long. The amount spent per road-length unit is therefore small, which means the Snow Management Unit does not rise. If it is difficult for such remote municipalities to increase their budget, it may be necessary to take other measures, such as reorganizing a village in order to shorten the road length between households. Further studies are needed to show how differences in Snow Management Units affect life, welfare, and normalization in areas with heavy snow fall.

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We developed an icicle/frost heave prevention system aided by a heat pipe for lining of railway tunnels. To evaluate the system, we installed test pieces in an existing tunnel and measured their temperatures. Furthermore, its effect was confirmed through a numerical simulation of heat transfer using a one-dimensional unsteady-state model. On the basis of the results of field test and simulation, it is concluded that the developed system effectively prevents icicle/frost heave.

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