Lilley, CR, Roberts, T, Putzar, G & Beck, DA 2013, 'Dynamic simulations of excavations with yielding bolts', in Y Potvin & B Brady (eds), Ground Support 2013: Proceedings of the Seventh International Symposium on Ground Support in Mining and Underground Construction, Australian Centre for Geomechanics, Perth, pp. 525-538, https://doi.org/10.36487/ACG_rep/1304_36_Lilley
(https://papers.acg.uwa.edu.au/p/1304_36_Lilley/)
Abstract: We describe 3D simulations of rockbolts installed in a tunnel intersection geometry in a jointed rock mass subjected to an extreme dynamic loading event. A newly developed yielding rockbolt was simulated, using a bolt model calibrated from laboratory drop tests. The results show that most of these yielding bolts can still retain load carrying capacity even with up to 1 m of closure, for the simulated conditions. The same dynamic simulation using fully encapsulated resin grouted rockbolts indicated that a significant fraction of resin bolts fail at ~100 mm of closure. The simulations demonstrate several important components of a framework for realistic simulations of excavations and ground support systems subjected to dynamic loading. Many parts of this framework are proposed as technology development directions, and combining all parts into workable simulations will indeed be challenging. However, for critical excavations, such sophisticated analyses may be justified.