Monitoring systems have been installed at Grimselpass near Innerkirchen in the Berner Oberland, Switzerland by ALPUG, an alpine natural hazards research organization. The mountain pass road, a busy tourist route in the summer, lies in the path of potential rock falls. The site consists of two enormous vertical rock plates, roughly 200 m high, with ever-widening cracks at the back. The cracks are opening at a rate of up to 1 mm per day and are already more than 3 m wide. To monitor the rock movement, two Campbell Scientific data loggers are connected by a radio modem to the traffic lights on the main road. If there is a significant increase in the opening of the crack, or the control wires break, an alarm is sent to the lights within 1 second. It is estimated that it takes 30 seconds for falling rocks to hit the main road, so this allows for the lights to stop the traffic going through to the danger area.



Surveillance du mouvement d'un mur colossal de roche


Col du Grimsel près d’Innerkirchen dans l'Oberland bernois, Suisse


Campbell Scientific Ltd.

Organisations participantes


Paramètres mesurés

Chute de roches

Dispositifs contrôlés

Feux de circulation (pour empêcher les automobilistes de pénétrer dans la zone de chutes de pierres)