Bruning, T, Orrego, C, Vejrazka, C & Sanker Pararath, G 2026, 'A framework for airblast analysis and risk management for early-stage caving', in A van As, D Cumming-Potvin & J Wesseloo (eds), Caving 2026: Proceedings of the Sixth International  Conference on Block and Sublevel Caving, Australian Centre for Geomechanics, Perth, pp. 1-14, https://doi.org/10.36487/ACG_repo/2645_13
(https://papers.acg.uwa.edu.au/p/2645_13_Bruning/)
Abstract: Managing the airblast principal hazard through the establishment of a cave is essential to mitigate operational risk to personnel and infrastructure. Early stages of undercutting and cave propagation present unique risks due to the low height of the muckpile, and the uncertainty in early measurements to confirm cave initiation. Currently there is a lack of reliable data and many assumptions that need to be input into airblast models, which results in inherent uncertainty in the calculation of the risk that is not well understood. The proposed process outlined in this paper looks to address these concerns and presents the strategies developed during the cave establishment process for the PC2-3 cave at Cadia Valley Operations in New South Wales, Australia.
The proposed methodology first collects data from multiple monitoring and material movement tracking sources and compiles them into one model for cave back position and airgap volume estimation. Then using the geometrical estimates of the status of the cave, a VentSim™ CAST model is developed to enable the modelling of airblast velocities and pressures which may be experienced in the event of a sudden cave crown collapse. The results from data collection and modelling are then incorporated into an early caving airblast risk framework, where feasible failure mechanisms are considered alongside the theoretical calculations to derive implementable controls for effective management of the hazard.

Keywords: airblast, block caving, cave initiation, risk management