APPROACHES FOR ROCKFALL RUN-OUT CALCULATION AND UNCERTAINTY IN ROCKFALL STUDY

In mountainous areas, rockfall happens suddenly and occurs frequently, with the diverse kinematic characteristics such as free fall, sliding, rolling and projectile motion and the stochastic characteristics. Due to the diversity of factors, random motion and uncertainty in the study, it is still a big problem that how to predicate rockfall characteristics accurately. The problem leads to the truth that calculated results could not match the actual characteristics, and further leads to the phenomenon that countermeasures failed to prevent rockfall and rockfall disaster occurred often. Based on the summary of rockfall run-out calculation approaches in the past, we analyzed the applicability of different methods. Combing with case analysis, we found much uncertainty in rockfall study including cognitive uncertainty and random uncertainty. We proposed the idea that: the establishment of uncertainty view, theory and approaches in rockfall study is one of effective ways to promote the development of scientific prediction and prevention for rockfall. The study would provide reference for selection of appropriate rockfall calculation method and reasonable decision for rockfall prevention and mitigation.