Patterns of soil deformations around tunnels. Application to the extension of Madrid Metro
In the period 19951999 more than 30 km of new tunnels have been constructed for the Madrid Metro. Most of them are excavated with EPB shield through stiff Tertiary layers. The paper presents the application of numerical and analytical solutions to the soil deformations measured during these works. About 60 test sections have been analysed, some of them including measurement of vertical and horizontal displacements within the ground. The values of the solution parameters (ground loss, tunnel ovalization, soil volumetric deformation) have been obtained by fitting the measured movements. The variation of all of the parameters with tunnel geometry and soil type is discussed.
soil deformation analytical solutions soft ground tunnels subsidence