In this project we intend to develop numerical methods as well as a software code for the simulation of the three-dimensional motion of polygonised objects with frictional unilateral contacts. These methods will be tailored for and applied to the simulation of runout lengths of rockfall in hazardous areas in Switzerland. The non-smooth dynamics approach, which combines a rigid-body approach with "hard" contacts, has been successfully applied to multi-body systems with a few or moderately large number of bodies and a rather simple contact geometry (balls, rods, blocks). Many industrial problems (such as gears in contact) and real-life applications (e.g. the motion of non-spherical rocks on an uneven slope) demand the simulation of much more complex contact geometries and a much larger number of contacting bodies or contact points. The aims of this project are twofold:

	to develop numerical methods for the simulation of a large number of polygonised rigid bodies with complex geometries using set-valued contact laws in an efficient way, which involves the efficient calculation of contact distances between a large number of vertices and the adaptation of parameterisations to describe 3D rotations to fit within the non-smooth dynamics approach,
	to develop a tailored software code for the simulation of runout lengths of rockfall using 3D terrain data of high-risk areas in Switzerland and to experimentally verify the numerical results using SLF/WSL laboratory facilities.

The research project is conducted in the form of a doctoral dissertation at the ETH Zurich under the guidance of PD Dr. ir. habil. R. I. Leine and in close cooperation with Dr. A. Volkwein and Dr. P. Bartelt of SLF/WSL.

The Gurtnellen rockfall incident (photo SLF/WSL)

Simulation of rockfall (left) and thousands of blocks (right).

Publications:

Schweizer, A.: "Kontakt zwischen Körpern mit triangularisierter Oberflächenrepräsentation", Master thesis at the Center of Mechanics, ETH Zurich, 2008.