Upper bound analysis of collapsing blocks
Under the presence of velocity discontinuous surface in a limit state, the potential blocks tend to fall from the hanging wall of an excavation.
Combining with Hoek-Brown failure criterion, the rate of energy dissipation created along with detaching line was calculated in where detailed calculation process is presented with clear reasoning.
The whole rate of energy dissipation caused by internal forces can be integrated over two different parts with various parameters, and it results.