Authors: Khodayari, F; Diering, T

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Khodayari, F & Diering, T 2022, 'Material flow simulation using marker mixing', in Y Potvin (ed.), Caving 2022: Fifth International Conference on Block and Sublevel Caving, Australian Centre for Geomechanics, Perth, pp. 1387-1396,

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Material mixing and its impact on the block cave operations is one of the main aspects for evaluating and operating any caving project. Initial modelling with limited geotechnical data and calibration using the actual data are the two main phases to build the flow model. Challenges on the way are inevitable; how to predict the flow in the first place, and how to calibrate even when such data is available. In order to achieve realistic results, the right tools are a necessity to be able to mimic the actual cave. Vertical Mixing (VM), Template Mixing (TM), and CA3D tools in GEOVIA PCBC have been extensively used for more than two decades by many users across the globe; very useful tools but slow and limited on graphics. To overcome these challenges, Marker Mixing (MM) was introduced in 2021; a powerful material flow simulator with unique graphical capabilities and much higher speed compared to other existing tools. The stand-alone feature in MMIX provides the option to run a mixing model without even running a productions schedule. Implementing cave back and other geotechnical and operational constraints are easier and visually assessable, increasing the transparency while making it possible to improve the caving model in a more efficient approach. Markers simulate the material movements from their original location to extraction (from drawpoints) within the cave. Simulation is done step by step with vertical and horizontal movements, toppling, riling, erosion and frozen concepts all captured and visualised in the new MMIX tool. The theory and experience behind MMIX can help define the initial flow model, then in the next step, actual production data can be used to calibrate the parameters. In addition, information gathered from Beacons (smart markers) installed in the cave zone can be visualised, interpreted, and implemented using the MMIX play back tool. This feature can significantly improve the calibration process for achieving more precise models by mimicking the actual flow in the cave. The residual block model can also be generated using MMIX much faster and with better visual checks compared to CA3D. This paper introduces Marker Mixing tool, its features, and capabilities, with comparisons to existing Vertical Mixing, Template Mixing, and CA3D tools in PCBC.

Keywords: block caving, material flow, marker mixing, production schedule, PCBC

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