Development of in-situ rock stress map of south-western part of Norway

Abstract

Knowledge of in-situ rock stress is important for underground projects like mining, nuclear repository, hydropower and other utility tunnels and caverns for the assessment of stability condition. Specifically, it is very important to know the minor principal in-situ rock stress for the design of unlined pressure tunnels and shafts. If a rock stress map is available, it provides an approximate knowledge about the magnitude and orientation of in-situ rock stress and helps to plan and design the underground structures. This manuscript presents the methodology for developing in-situ rock stress map for south-western part of Norway where many unlined pressure tunnels and shafts of hydropower projects are located. The development of such map is believed to be useful for both early-stage planning of underground waterway system of hydro-power projects as well as for mining and civil engineering underground projects where in-situ rock stresses information is needed.