Design optimization of access roads and networks in hard-rock underground mines

The mineral industry is a significant part of the Canadian economy and contributes to the wealth and prosperity of Canadians. Underground mining operations have important challenges. The commodity prices have been quite low for the last five year. Operating costs continuously grow due to high energy costs and increasing depth. To remain business, underground mining operations need to find new ways of doing such that productivity and efficiency of the operations will be enhanced. New optimization tools and technologies present great potential to manage "new ways of doing". This research proposal aims to develop an optimization tool for access road network used for material handling and ventilation in underground mining. The research will start to explore a decision support tool for selection of central access as shaft or adit, and its dimensioning. This selection will reduce the size of the problem. Then, using emerging approaches in the Steiner tree and Dubins planning path algorithms, the network optimization will be fulfilled. The problem will be formulated as the minimization of haulage costs under constraints of minimum turning radius, maximum gradient, stability requirements, and production capacities. In the second stage of the research, the focus will be the integration of network optimization with the previously solved stope layout and sequencing optimizations such that a global optimization for underground mine planning is attained. The objective will shift from cost minimization to maximization of net present value. For this reason, a framework based on a divide and conquer approach will be constructed, and the framework will be solved by parallel simulated annealing. The main idea behind this solution approach is to parallelize three sub-problems of underground mine planning in such a way as to reach the optimality in a reasonable time. At the end of this research, an optimization tool will be delivered to Canadian mining operations. Also, the research outcomes will assist in diversifying the product portfolio of the mine planning software industry.