Abstract
To effectively mitigate the rockfalls from the slopes neighboring railway lines, the risk of individual rock should be quantified with consideration of its stability and damage cost, and then the risk-based counter action should be done. However, assessing all the rocks in all the slopes along with the lines is quite difficult due to the restriction of budget and human resources. Therefore, in this study, two-step risk assessment was proposed: first, the target lines to be assessed were preliminarily selected according to the expected number of rockfalls which can be calculated by previous data. Then the risk of individual rockfall in the target lines was calculated by multiplying the damage cost and the collision probability between the rock and train. Finally, optimum counter action was determined according to the risk reducing effect or its benefit by cost.
