Improved analytical solutions for the response of underground excavations in rock masses satisfying the generalized Hoek-Brown failure criterion

Analytical solutions for tunnel design are widely used in practical engineering, as they allow a quick analysis of design issues such as estimation of support requirement. In recent years, several papers analyzing the behavior of rock masses that obey the conventional or generalized Hoek-Brown criterion have been published. This article presents a complementary analysis that includes a new normalization of the generalized Hoek-Brown failure criterion, complete solutions for associated and non-associated flow rules, with some new closed-form solutions in the latter case, and in-depth considerations regarding intermediate stresses and edge effects. The results obtained show full agreement with existing solutions in the literature, when possible, and with numerical finite element models in cases that had not been treated previously.