Full-scale simulation and validation of bucket filling for a mining rope shovel by using a combined rigid FE-DEM granular material model

Rope shovels and other heavy mining equipment used for loading fragmented rocks to extract minerals from the earth are used in almost every open pit mine. The optimization of the loading process is of enormous value due to the extremely large amount of material turn over. In this work, a full-scale numerical model of the loading process is developed. Granular material of copper ore is modeled in a combination of rigid finite elements for larger particles with complex shapes, and the discrete element method for smaller particles. A multi rigid body dynamic model, discretized with finite elements are used to model the rope shovel. Calibration of the numerical model for the granular material is performed via a new and unique experimental full-scale approach of analyzing waste rock pile angles with a height of approximately 15 m. In situ experimental data acquisition is performed during the loading process for validation of the model. After model validation, the influence of several loading variables such as bucket rake angle, velocity, and position from the pile are investigated and evaluated. When comparing the numerical model results with experimental mass measurement an excellent agreement was observed. Also, drone camera video recordings of the mass flow behavior and the numerical mass flow behavior are in agreement. Small adjustments of dig variables show a significant effect on the average dig force as well as the bucket fill factor.

Automated summary

This work developed a full-scale numerical model to optimize the loading process in mining, using rigid finite elements and discrete element method to model copper ore granular material and rope shovel. The model calibration was done by analyzing waste rock pile angles, and validation was performed with in situ experimental data. The influence of loading variables such as bucket rake angle, velocity, and position from the pile were investigated.