Beck, DA, Kassbohm, S & Putzar, G 2010, 'Multi-scale simulation of ground support designs for extreme tunnel closure', in Y Potvin (ed.), Proceedings of the Second International Symposium on Block and Sublevel Caving
, Australian Centre for Geomechanics, Perth, pp. 441-453.
The numerical simulation of ground support requires that the ground deformation and support response are both captured accurately. The mechanisms of rock mass damage, dilation and deterioration must first be simulated sufficiently to produce realistic tunnel deformation in 3D, then the physical response of the support elements must be realistic if the support and loading systems will come to a realistic equilibrium.
This requires the simulation of rock mass and mechanical behaviour on a number of different length scales and demands a level of similitude that is not commonly implemented for mine models. The load-displacement response of both the support and the rock mass around excavations must be correct for the models to be valid.
A multi-scale approach to mine deformation modelling can be used to improve the similitude of capacity and demand simulation of ground support. Case studies are used to demonstrate the behaviour of several heavy support systems using this approach. Some proposed support designs for a deep cave subject to high stress and expected significant drive closure are tested and the limitations and vulnerabilities of the support systems are exposed.
The modelling methods used to simulate the mine deformation, drive behaviour and support system response are discussed and some sufficiency requirements for similar analysis are highlighted.
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