Analysis of shallow-tunnel entrances with numerical three-dimensional simulations
The construction of a relatively shallow mining tunnel in Brasilia was done under challenging ground conditions. After the end of the construction phase, numerical simulations were performed to compare the real settlements occurred on the tunnel entrances with the predicted settlements of the numerical analysis. These analyses were three-dimensional. The adjustment of the on-site instrumentation and the software output was good for engineering purposes. The proximity of the results was possible by the knowledge, by the authors, of the parameters used in the primary design and because of some modelling techniques, specially a simplified way to model pre-support interventions adapted from Hoek (2003), described in the article.