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Show Fig. 2. ( Left) View toward the avalanche path above the Dalaas rail station. Fig. 3. Longitudinal profile of the avalanche path above the Dalaas rail station ( Arlberg line), scale 1: 8000. Ordinate -- meters above sealevel. Lawine ~ avalanche. Bahnhof- Gebaude Dalass - Rail station building Dalaas. Stellung des Zuges - position of the train. Because of the existence of openings in the wall, its strength is very much reduced, so that the buckling strength of the timbers no longer is the determining factor, but the forces must be absorbed by the tenons of the vertical beams. The given pressure is to be considered therefore as the upper limit, which probably was at most only halfway reached. From the established destruction, as well as from the existence of intact window panes in the front and side walls, it is concluded that upon the striking of the avalanche no impact stresses occurred. On the contrary, the events must have started so slowly that they may be calculated as static compressive load. The destruction of the back gable wall and of the roof sheathing indicates an upward acting component of force. With the house furnishings and the snow load, without the foundation, the weight of the house would be estimated at between 40 and 50 tons. For tipping about the leading edge, a vertical force of about 20 to 25 tons was thus necessary, which would correspond to an upwards directed component of force on the rear facade surface of about 650 to 750 kg/ m2. •• Fig. 4. Mesmerhouse in Blons. The house, of log construction, was raised in its entirety from the foundation, moved to a side slope where, as a result of the sloping position, the upper story slid off from the rest of the house. At the right the building wall facing the avalanche. 5 |