Analysis of rockfall risk on mountainside roads: evaluation of the effect of protection devices

Many kilometres of roads are close to rock slopes that are prone to rockfalls. The fulfilment of safety requirements in such situations is a multidimensional design process involving public and private technicians in the assessment and management of the problem. In this paper, a rockfall risk management approach has been applied to the road infrastructure network of the Regione Autonoma Valle D’Aosta, in order to calculate the level of risk and of its reduction using rockfall protection devices. In order to better understand the methodology, a comparative analysis of road accidents in Aosta Valley has been discussed. The road risk assessment was developed taking into account the absence of rockfall protection devices, and when they are present, different levels of efficacy have been considered.