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Joints and faults are inherent part of the rock mass. In the vast majority of mining slopes, discontinuity structures play an important role in slope stability and may trigger a slope failure. The most important step in understanding the slope failure mechanism is to have a reliable model, which shows how all the discontinuity sets are constituted in the rock mass and how they interact with each other. However, building a fracture model is not a straightforward process, since it needs to combine discontinuity information from a variety of sources, such as detailed slope mapping, borehole logging data and remote sensing technologies. Hence, this manuscript attempts to develop a comprehensive structural model of the complete mine area in an open pit, which is the biggest in Norway with respect to its depth and area of coverage. The manuscript demonstrates on how it is possible to consolidate information from different sources in order to identify typical orientation of the detailed fractures that are associated with the main structural lineaments. The process involves analysis of different sources of data in order to correlate this information into useful evidence about the orientation of the fracture systems in terms of dip and dip direction. Further, the mine is divided in different structural domain and a 3D structural model is developed. As an end result, the domains are kinematically tested with respect to different types of failure modes in both overall slope and bench slope scale of the mine for both hanging wall and foot wall. It is highlighted here that the results presented in this manuscript are the part of the research project called "Decisive Parameters for Open Pit Slopes (DePOPS)".

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Just south of Oslo Central Station, the new high-speed Follo Line railway tunnels pass beneath the existing Ekeberg road tunnels. This paper presents the construction methods, numerical model, and monitoring program used to assess the stability of the E6 road tunnels during the excavation of the Follo Line tunnels only a few metres below. The construction of the Follo Line was approved subject to three conditions: (1) there should be no negative effect on the stability of the Ekeberg tunnels, (2) the traffic flow in the Ekeberg tunnels had to be maintained at all times and (3) any risk of instability in the existing tunnels must be detected beforehand, so that necessary precautionary actions could be taken in good time. To deal with the challenges, SINTEF developed a comprehensive analysis procedure, combining continuous rock stress measurements and displacement measurements with 2D and 3D numerical modelling. The rock stress change monitoring was used together with the numerical model to monitor the stability conditions in the Ekeberg tunnels as the Follo Line tunnels were excavated. This ensured that any risk of instability in the existing tunnels could be detected in advance to enable precautionary action to be taken. The successful completion of the new tunnels without any disturbance to the road tunnels shows that the procedure would be useful for dealing with similar applications in the future.