Hebert, Y & Sharrock, G 2018, 'Three-dimensional simulation of cave initiation, propagation and surface subsidence using a coupled finite difference–cellular automata solution', in Y Potvin & J Jakubec (eds), Proceedings of the Fourth International Symposium on Block and Sublevel Caving
, Australian Centre for Geomechanics, Perth, pp. 151-166.
This paper outlines a new methodology for modelling caveability and subsidence using bi-directional coupling between the continuum code FLAC3D and the cellular automata code CAVESIM. FLAC3D, using the CaveHoek constitutive model, simulates the progressive failure and disintegration of the rock mass from an intact/jointed to a caved material. CAVESIM simulates gravity flow, in particular the collapse, bulking and movement of caved rock. The coupled method captures many important aspects of caveability affecting cave design such as hang-up formation, material recovery, timing of surface breakthrough or interaction with other lifts, crater development, and surface subsidence. The key to improved modelling of many of these aspects is the ability to accurately capture the impact of draw and gravity flow on cave propagation and subsidence.
Keywords: numerical modelling, caveability, subsidence, gravity flow
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