Coupled DEM-FEM approach for rockfall protection structures

Rockfall impact scenarios represent an immense danger for humans and infrastructure, especially in mountainous areas. If the cause of the rockfall cannot be prevented, protection structures are installed in exposed areas. Due to the arbitrariness of the rock size, the impact position, and the impact velocity, no general, simplified load approaches are available. To analyze rock impact on protection structures, numerical methods are needed. Recently we demonstrated how to combine the DEM and the FEM in a partitioned coupling environment to simulate the strong interaction between impacting rocks and the appropriate protection structures. We concentrate on highly flexible protection nets as they prove to be the most efficient constructions for absorbing large amounts of energy. Their flexibility allows extensive deformations, extending the braking time and thus reducing peak forces and stresses during the impact. The particle method DEM is used to model and simulate the impacting object and calculate contact forces. Modeling the rock shape with clusters of single spherical discrete elements, we can consider arbitrary shaped rock geometries while keeping the efficient contact algorithms of single spheres. At the same time, the protection nets are modeled with the help of the FEM. The high flexibility of the protection nets calls for sophisticated construction details, such as braking elements, sliding nodes on edge cables, and unique material laws. The FEM can fully meet these requirements. In this talk, we will present the results of recent publications in which we demonstrate the practical application of the proposed coupling scheme for real-world application cases, including experiments conducted in the Swizz Alps.     «

Rockfall impact scenarios represent an immense danger for humans and infrastructure, especially in mountainous areas. If the cause of the rockfall cannot be prevented, protection structures are installed in exposed areas. Due to the arbitrariness of the rock size, the impact position, and the impact velocity, no general, simplified load approaches are available. To analyze rock impact on protection structures, numerical methods are needed. Recently we demonstrated how to combine the DEM and the...     »