The research presented in this dissertation consists of four topics. The first of these topics is an experimental study of rock fracturing due to rapid thermal cooling, and the other three topics are related to mine-to-optimization. This includes the development and testing of a site-specific model for blast fragmentation, the development of a technique for utilizing digital image processing and ground-based LIDAR for rock mass characterization, and an experimental study of the effects of ore blending on mineral recovery. All four topics are related through the subject of rock fracturing and rock fragmentation. The results from this research are important and can be used to improve engineering design associated with rock excavation and rock fragmentation. First of all, a successful set of laboratory experiments and 3D numerical modeling was conducted, looking at the effects of rapid thermal cooling on rock mechanical properties. The results gave the unexpected finding that depending on the rock type and the thermal conditions, rapid cooling can result in either overall crack growth or crack closing. Secondly, a site-specific model for predicting blast fragmentation was developed and tested at an open-pit copper mine in Arizona. The results provide a practical technique for developing a calibrated blasting model using digital images and digital image processing software to estimate in-situ block size, and a calibrated Schmidt hammer to estimate intact tensile strength. Thirdly, a new technique was developed to conduct cell mapping in open-pit mines using the new technologies of digital image processing and ground-based LIDAR. The results show that the use of these new technologies provide an increased accuracy and the ability for more sophisticated slope stability analyses with no increase in field time only a moderate increase in data processing time. Finally, a successful set of laboratory experiments was conducted looking at the effects of ore blending and grinding times on mineral recovery from a set of six ore from a copper mine in Arizona. The results gave the unexpected finding that for a fixed grinding time, the mineral recovery of the blended ores exceeded the average of the individual recoveries of the same ores unblended.

Este trabalho tem seu foco no problema de sequenciamento e programação da lavra em mina a céu aberto, com alocação de equipamentos de carregamento. Neste estudo considera-se a existência de uma frota heterogênea de equipamentos de carga e dois tipos de material lavráveis, sendo minério ou estéril. Para a lavra de minério são considerados requisitos de qualidade a serem atingidos pela mistura de minério, um britador, uma capacidade de operação atribuída à usina de beneficiamento e uma pilha de estoque objetivando abastecer a usina quando faltar minério nas frentes de lavra, denominada pilha de ROM. Em uma mina o carregamento pode ser gerido por um plano de lavra que descreve a movimentação e a produção horária de cada equipamento de carga ao longo do tempo. Neste contexto, apresenta-se um modelo matemático apoiado por um algoritmo responsável por mover o horizonte de tempo a cada execução do modelo com intuito de gerar ordens de lavra resolvidas com otimalidade. Juntas, essas ordens descreverão o plano de lavra dos equipamentos de carga. Os experimentos computacionais, realizados utilizando dados de uma jazida de cobre, mostram a efetividade da proposta considerando um horizonte de médio prazo. / This paper focuses on the mining scheduling problem in open pit, considering the allocation of loading equipment. This study considers the existence of a heterogeneous fleet loading equipment and two types of mineable material, namely ore or waste. For the mining of ore are considered quality requirements to be met by the ore blending, a crusher, the capacity of operation of the processing plant and a stockpile which feed the plant when there is lack of ore in mining fronts, called ROM stockpile. In a mine, loading can be managed by a mining plan that describes the movement and the schedule of each load equipment over time. In this context, we present a mathematical model supported by an algorithm that is responsible for moving the time horizon for each model run, with the goal of generating mining orders till resolved to optimality. Together, these orders describe the mining plan of the loading equipment. The computational experiments, conducted using data from a copper deposit, show the effectiveness of the proposal considering a medium-term horizon.

Este trabalho tem seu foco no problema de sequenciamento e programação da lavra em mina a céu aberto, com alocação de equipamentos de carregamento. Neste estudo considera-se a existência de uma frota heterogênea de equipamentos de carga e dois tipos de material lavráveis, sendo minério ou estéril. Para a lavra de minério são considerados requisitos de qualidade a serem atingidos pela mistura de minério, um britador, uma capacidade de operação atribuída à usina de beneficiamento e uma pilha de estoque objetivando abastecer a usina quando faltar minério nas frentes de lavra, denominada pilha de ROM. Em uma mina o carregamento pode ser gerido por um plano de lavra que descreve a movimentação e a produção horária de cada equipamento de carga ao longo do tempo. Neste contexto, apresenta-se um modelo matemático apoiado por um algoritmo responsável por mover o horizonte de tempo a cada execução do modelo com intuito de gerar ordens de lavra resolvidas com otimalidade. Juntas, essas ordens descreverão o plano de lavra dos equipamentos de carga. Os experimentos computacionais, realizados utilizando dados de uma jazida de cobre, mostram a efetividade da proposta considerando um horizonte de médio prazo. / This paper focuses on the mining scheduling problem in open pit, considering the allocation of loading equipment. This study considers the existence of a heterogeneous fleet loading equipment and two types of mineable material, namely ore or waste. For the mining of ore are considered quality requirements to be met by the ore blending, a crusher, the capacity of operation of the processing plant and a stockpile which feed the plant when there is lack of ore in mining fronts, called ROM stockpile. In a mine, loading can be managed by a mining plan that describes the movement and the schedule of each load equipment over time. In this context, we present a mathematical model supported by an algorithm that is responsible for moving the time horizon for each model run, with the goal of generating mining orders till resolved to optimality. Together, these orders describe the mining plan of the loading equipment. The computational experiments, conducted using data from a copper deposit, show the effectiveness of the proposal considering a medium-term horizon.