Regional-scale numerical stress model of the Stockholm area
New metro lines are planned in Stockholm, comprising a total length of approximately 20 km with 10 new stations, mostly located underground. One of the new lines will pass under Saltsjön (a bay of the Baltic Sea) and through a major regional fault. The stress magnitudes and orientations around the fault are highly uncertain, and stress measurements are not practically possible near the fault. To quantify possible stress conditions near the fault, a regional-scale stress analysis was conducted, using three-dimensional numerical modeling. The model included a total of 14 faults, and the rock mass was represented as one unit. Calculated stresses at the location of rock stress measurements were evaluated and compared to the measurements. The stresses around two new metro stations were also evaluated and compared to local-scale models of these stations. The results will be a part of the input data for further design of the metro tunnels passing the major faults and the new metro stations.