Evaluation of impending collapse in circular tunnels by analytical and numerical approaches

On the basis of a straightforward analytical approach which has been recently proposed by the present authors, a comparison with numerical procedures to predict plastic collapse in circular rock tunnels is reported. In fact, numerical modeling of the evolution of progressive failure leading to collapse in tunnels is a quite complicated matter and requires great care in modeling the problem and interpretating the results. In order to provide a guide to engineers facing rock limit state problems, a few examples by means of three commercial packages are presented, discussed in details and confronted with the analytical results.

► Numerical modeling of progressive failure leading to collapse in tunnels is a complicated matter.
► Great care is required in modeling the problem and interpretating the results.
► A comparison between analytical and numerical procedures is presented and discussed in details.