Haulage drifts are used for the transportation of blasted ore from the draw point to nearby ore pass or dumping point in sublevel mining systems. During production, haulage drifts are occupied by mine operators and haulage equipment. Therefore the stability of haulage drifts is important to the safe and uninterrupted production of a mining operation. It would be advantageous to know a priori how drift stability is influenced by mining activities in the proximity of the drift. This thesis presents the results of a study to examine drift stability and rock support system performance of a haulage drift, based on a case study of Garson mine from Vale Inco, Sudbury, Canada.;Much information is gathered from the mine site to help understand the entire mining environment. Parameters like rock mass character, mining plan and stress environment need to be known ahead of time in preparation for building the numerical model. Consequently, a geomechanical database named " Data Integrator for Mine Analysis and Design (DIMAND)", including the most important features related to mining activities, has been developed.;Numerical modeling results reveal that there is a dominant trend of low stress regime (postpeak) in the drift back, which results from the stoping activities in both cases of low and high horizontal to vertical in situ stress ratios. There is a gradual spread of yielding around the haulage drift with mining activity. However, it is not until the nearest two stopes are mined and backfilled that the haulage drift is affected severely with yielding extending from the drift toward the orebody. Significantly higher wall convergence ratio of the haulage drift is noticed when the nearest stope to the haulage drift is mined.;The FLAC modeling study on rock support performance reveals that primary support alone is not sufficient to take on the full duty of the haulage drift during the life of a mine plan. When the enhanced support system is installed, the total support system is capable of sustaining mining induced loads to the end of the planned mining sequence. The system performance may be further improved if the enhanced support is placed after the first stope was excavated, at lower level to the haulage drift, has been mined out and backfilled. Shotcrete plays an important role in the enhanced support system performance. The highest stress in the shotcrete layer is located at the left upper corner of the drift toward the orebody contact and occurred at the end of the mining sequences.;The Mohr-Coulomb and Hoek-Brown models are the most widely used constitutive laws to describe the elastoplastic behaviour of rock materials under load. They are available in many numerical modeling codes including Phase2 and FLAC, which were selected to perform the numerical modeling analyses in this thesis. Consequently, the Mohr-Coulomb and Hoek-Brown constitutive models are reviewed in the first place. The finite element method is selected, together with Hoek-Brown model, to study the influencing factors of stability of haulage drift; finite difference method is chosen, along with Mohr-Coulomb model, to examine the performance of rock support system design.
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