An approach for Evaluating the Full Truck and Full Bucket Loading Strategies in Open-Pit Mining Using a Discrete Event Simulation and Machine Learning
Creators: Al-Masri, Mohammad
Publisher: name: University of Alberta Library
Year: 2022

<p>Material loading and hauling are crucial factors in the mining industry, comprising over 50% of the costs. Many studies covered optimization and improving the efficiency of truck-shovel operations. Decreasing operating costs is vital for mining companies to remain profitable and feasible. Truck-shovel operations efficiency affects the complete mining operation, from equipment performance through productivity to the final mill throughput. Autonomous trucks and shovels and the digitalization of mines are taking place now to reduce costs, increase safety and contribute to sustaining the environment. Operation uncertainties are a source of risk and pose a threat to the continuity of the operation. Enhancing mining and loading operation due to the high contribution in operating costs, which require mining projects to look for alternatives or real options when uncertainties are encountered; for example, equipment availability deteriorates with time or a queuing condition results in a change in mining operation. A proper decision should be involved in regarding the loading strategy.<br>
This research evaluates the alternative options under uncertain conditions related to the shovel in mine. In addition, the research tries to answer the question of what will happen if a specific loading scenario in operation is run for a set of time, by developing and implementing a framework that considers the loading strategies and accounts for material properties and operator efficiency. Then a decision on a proper loading strategy based on these inputs in a short-term period will be recommended. Next, the machine learning model predicts the proper strategy and evaluates the feature importance based on the provided data. Through this study, a truck-shovel model was simulated using the Haulsim simulation software to create the production rates, cycle times and anticipated costs for each loading scenario in order to investigate the sweet spots between these scenarios and the controlling key performance indicators in an open-pit mine.<br>
The proposed operation concepts of loading strategies are full truck and full bucket, which is a term called on shovel passes to the truck; full truck requires the highest passes to fill the truck, so the truck travels full and full bucket lower passes truck travel under full due to queueing conditions or production issues. Equipment selected in a mine with a different fleet size are run in a simulation to understand the full truck and full bucket.<br>
The study results indicate a sweet point incorporated with changing the match factor between loading strategies; a huge decrease in haulage costs by ~ 25% and queueing trucks reduced by 50% in the simulation results. Moreover, the investigation of changing the capacity of the shovel, rolling resistance and haul roads is embedded as a sensitivity analysis in this work. Next, these outputs are trained and tested in a machine learning model in order to predict the loading strategy, whether full truck or full bucket. Moreover, signifying the most important feature affecting the prediction by using feature importance techniques, the feature was the cycle time in the case study. These conceptualized terms (full truck and full bucket) and the developed framework can integrate with autonomous trucks and shovels because decisions are easier to take than manually operated machines.</p>