Avalanche Doppler Radar Monitoring - Long Term Velocity Measurements at the Vale de la Sione

640-643

Artikel aus einem Buch

200204846

ABSTRACT: In this contribution we present Doppler radar data obtained over multiple years in terms of
total radar intensities and material velocities. These give an overview of the avalanche movement and allow
characterizing typical avalanche velocities for various avalanche flow regimes. In the data analysis we survey
the ratio of frontal approach to material velocities for the observed natural and artificially released avalanches.
Measurements from over 40 avalanches, without distinguishing between various types of flow regimes, show
that the maximum along the entire path of the main material velocity is on average approximately 5 m/s higher
then the maximum frontal approach velocity. Local peak velocities may exceed the maximum of the main
material velocity. The knowledge of the different avalanche velocities and their ratio is of major importance for
practitioners and engineers since the material velocity, rather then the front velocity, determines the resulting
impact pressure on buildings and structures. The presented data are the base for a future online repository.
This open source material can be used for the calibration, parameter optimization and further development of
avalanche simulation tools and their underlying process models.

Keywords: avalanche dynamics, radar measurement, velocity, avalanche head dynamics