Rockfall simulation with consideration of multi-blocks using 3D DDA and its application to countermeasures

Rockfalls are the most frequent, major hazards in mountainous areas. In order to assess the rockfall hazards and implement contermeasures to reduce the corresponding risks, it is necessary to evaluate the rockfall movement behaviors in advance which is largely dependent on numerical simulation. The dynamics of falling rocks is greatly affected by the spatial variability in 3D of both rocks and slope. However, previous models usually considered the rock block as a point or rigid sphere, which is not rational. Moreover, the multiple blocksin a rockfall event are modeled independently without consideration the complex interactions, say, the collisions among them. Thus, for more rational modelling rockfalls, this paperdevelops a new tool for 3D rockfall problems based on3D DDA which can cosider both the rock shapes and the collisions among falling rocks. The benefits of rockfall simulation using 3D DDA has been shown by:multi-blocks rockfall simulations. Fanally, as application, the simulation results are used to help the planning of countermeasures. The results show that the new rockfall tool using 3D DDA is more rational and effective.