The vulnerability of buildings affected by powder avalanches

The major problem in the estimation of avalanche risk is the evaluation of vulnerability, that is the degree of loss to a given element or set of elements at risk within the area affected by avalanches, because of the paucity of suitable data to evaluate the effects of avalanches on people and properties. Few are the studies about this component of avalanche risk, particularly concerning snow avalanche effects on "alpine-type" buildings. In the present work an empirical vulnerability relation for "alpine-type" buildings affected by powder avalanches is proposed, using the data from two catastrophic avalanches that occurred in Austria in 1988 and 1999. The curve is then compared to the theoretical estimate of the collapse load of non structural elements of the buildings affected by the Morgex avalanche, occurred in Aosta Valley (Italy) in 1999.