The Selection of Suitable Boundary Conditions for Finite Element Simulations of Deep Tunnels

In finite element simulations of deep tunnels an appropriate selection of the boundary conditions at the border of the model is important. Commonly, a system with vertically and horizontally fixed boundaries is used for finite element calculations of deep tunnels. In the contribution the shortcomings of this assumption will be explained and the requirements to the model size, which should be considered for this type of boundary conditions, are discussed. An alternative approach is also presented, which is derived from a commonly used approach for c and has been adapted to deep tunnels.