Abstract
From a reconnaissance of dangerous sites along national roads, the Ministry of Land, Infrastructure and Transport (formerly Ministry of Construction) has been pointing out those sites vulnerable to rock falls. On this process, in order to judge a priority of countermeasure, it is important to determine whether a site is dangerous or not by quantitative estimation to measure the risk of rock fall. This research proposes a risk evaluation method for rock fall on road slope. Features of this method are as follows. 1) The mechanical model according to the collapse mechanism of rock fall on site is defined, and a collapse risk evaluation in consideration of this mechanical model and the uncertainty of soil parameter is performed. 2) A quantitative evaluation of road disaster in consideration of the probability in which rock reaches the road and loss is performed. 3) By carrying out comprehensive evaluation of both evaluations, a risk of rock fall on road slope can be evaluated quantitatively.
