| Finite element analysis of tunnel excavations has been widely used by geotechnical engineers for assessing the deformations and stress conditions. Discontinuities in the rock mass play a major role when simulating the behaviour of the rock mass around an opening. A crucial point in such analyses is the choice of the constitutive model. Although numerical modelling of jointed rock mass has been suggested by several authors in the last three decades and different modelling codes have been developed, the simulation of discontinuities is still a complex task. After reviewing the various constitutive models, the author of this thesis presents the simulation of bedded rock mass based on the concept of an equivalent media proposed by Amadei and Goodman. The model has been implemented in a two-dimensional finite element code. In addition to the properties of the bedding planes, the spacing between them is considered. The performance of the model is shown by a parametric study focusing on the influence brought by the scale effect. For the latter control, a comparison with the results from the design of the Piora exploratory tunnel in the Swiss Alps has been carried out. |
