Soils reinforced by bolting - Numerical analysis and applications to the face of a deep tunnel

Soils or soft rocks reinforced with linear inclusions constitute a composite material which is difficult to numerically model, due to large contrasts between the deformation module and differences of scale. The homogenisation of recurring environments means that the behaviour of macroscopic materials such as these can be considered under certain conditions. In this article, the technique is described and the anisotropic behaviour of the homogenised material and its positioning in an axial symmetry numerical code is outlined. The comparison with a three-dimensional analysis of homogeneous loadings allows the limits of this approach to be studied. Lastly, the comparison of the homogenisation technique with three-dimensional modelling is carried out on deep tunnels reinforced at the coalface.