Characterisation of secondary fragmentation processes using a combination of laboratory experiments and numerical analysis

点击翻译按钮获取中文摘要

The development of a fragmentation model is critical to provide reliable estimates of fragmentation for use in mine planning. The model would need to provide a measure of the range and distribution of the sizes of the rock blocks expected to be produced at various stages during the mining processes. For block and panel cave mining, the size and shape of the blocks extracted from the drawpoints is of particular importance, since the production equipment and the drawpoint layouts must accommodate the resulting blocks. The disparity between fragmentation predictions assessed during mine feasibility and those encountered during caving underscore the need to better understand secondary fragmentation processes and mechanisms to facilitate the economic and sustainable mining of the resource. To address this need, funds and in-kind support have been provided by industry partners to support research at the University of British Columbia (UBC) that will focus on integrating numerical analyses and laboratory experiments to study the failure and comminution processes associated with rock fragmentation under different load conditions that parallel those encountered in a caved ore column. The research will use controlled experiments at different laboratory scales to calibrate and constrain a series of advanced numerical analyses simulating brittle fracture processes (using the state-of-the-art FEMDEM code ELFEN). These will be used to develop new tools and relationships for characterising secondary fragmentation for block and panel cave mine design. Building on this, a three-year NSERC Collaborative Research and Development (CRD) grant is proposed here that will work towards integrating sophisticated numerical methods with laboratory experiments to improve our knowledge of fragmentation processes for underground mass mining methods and its contribution to safe and economic mining. The key objectives of the CRD will focus on geostatistics based Discrete Fracture Network (DFN) models, rock breakage efficiency associated with veins density, and calibration of modelling results with experimental results.