Standardisiertes Einwirkungsmodell zur Bemessung von Wildbachsperren unter Mureinwirkung

Standardized load model for design of torrential barriers under debris flow impact

Torrential barriers with energy-dissipating, filtering or deflecting function for debris flow are subject to extreme dynamic stress that presupposes the application of high safety standards for design, construction and maintenance. The newly issued Austrian Standard ONR 24801 provides a standardized model for the design of torrential barriers under debris flow impact, which has been developed from comparative calculation of common debris flow models from engineering practice in torrent control and calibrated by impact measurements of debris flow events. The model is based on a combined static-dynamic stress approach and also takes into account the impulse by a single object (block, tree trunk). The dynamic part of the debris flow stress is transferred from a characteristic cross-section in the torrent to a vertical impact area of same dimension on the central part of the barrier; additionally static debris flow stress is applied. The standardized model was already tested successfully at several torrential barriers and is in good agreement with the common design approaches (experiences) of torrent control in Austria.