The history of stress around a circular tunnel during excavation in a homogeneous, isotropic, linear elastic or plastic medium with a strain softening behaviour, subjected to either isotropic or anisotropic state of stress, in 3D conditions are considered by using a 3D finite difference model. The results are presented by means of the stress path method with attention paid to the zones located in the crown/invert and in the springlines. It is shown that the stress path in these zones exhibits a more complex trend of behavior with respect to those typical of 2D simplified analyses. The study is to be used in connection with triaxial testing of marly-clay and clay-shales, with the purpose to investigate the behavior of these rocks in short term and long term conditions.
The history of s …
AUTORI: Barla M. RIG ANNO: 1999 NUMERO: 1 Numero di pagina: 53