A study on the behaviour of concrete lining and rock mass during shaft excavation at the Horonobe URL project. Part 2

The authors investigated concrete lining stress caused by excavation of a 6.5 m diameter access shaft at the Horonobe Underground Research Laboratory. They analyzed lining stress distribution by three-dimensional analysis. The stress distribution was also measured with ten stress meters installed in each section in the direction of maximum and minimum initial stresses. As a result, it was clarified that the maximum and minimum lining stresses occurred in the inner bottom in the direction of the minimum initial stress and in the inner top in the direction of the maximum initial stress, respectively, and the more than 10 MPa stress inclination between them occurred in 60 cm thick and 2 m high concrete lining. (author)