This thesis proposed a petrofabric classification of the rock mass domains and rock units encountered at the Birchtree Mine in the Thompson Nickel Belt (TNB), Manitoba. A program of field and laboratory studies has enabled the classification to be related to both geological and physical-mechanical properties. The classification has been aimed to advance TNB mining, mineral exploration and processing research. / The thesis also considers the genesis and nature of both inherent and mining-induced rock mass damage at the Birchtree mine. An inherent rock mass damage index, D$ sb{ rm I}$, has been derived, based upon the rock unit intact strength, together with the quantity and conditions of any meso- and macro-structure present. D$ sb{ rm I}$ was closely related to rock mass domains. The physical characteristics of rock mass damage in mine developments induced both through drill-and-blast and roadheader mining were also monitored at the Birchtree Mine. This permitted the formation of a mining-induced rock mass damage index, D$ sb{ rm M}$. This was based upon decrease in the intact strength, half cast/tool marks, normalized scaling time, drift condition rating, and orientation of local structure. The type and intensity of mining-induced damage was found to be clearly related to the nature of the rock mass units and domains, as evident in their inherent damage. / Two types of mining-induced damage mechanism were evident at Birchtree. Firstly, in the inherently weak rock mass ($ rm D sb{I}10$), such as the Metasedimentary Domain, the rock units are foliated with wider spaced joints. More energy is evidently required to fragment the rock mass through what was observed to be predominantly intact rock breakage controlled by foliation. These two damage mechanisms were also clearly evident from analysis of drift and fragmentation morphology survey data. The damage mechanism associated with both forms of mining appeared to be similar, although the intensity of machine-induced damage was significantly less. Rock mass damage related to ground stress redistribution was also observed. / This thesis was motivated by the need to understand, control and minimize mining-induced damage, particularly in serpentized ultramafic domains which will host most of the future TNB mining at depth. It thus concludes by reviewing a proposed strategy for rock mass damage sensing and control in underground development and stoping, based upon the experience at Birchtree.
| Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.40223 |
| Date | January 1995 |
| Creators | Paventi, Mario |
| Contributors | Scoble, M. J. (advisor) |
| Publisher | McGill University |
| Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
| Language | English |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Format | application/pdf |
| Coverage | Doctor of Philosophy (Department of Mining and Metallurgical Engineering.) |
| Rights | All items in eScholarship@McGill are protected by copyright with all rights reserved unless otherwise indicated. |
| Relation | alephsysno: 001485064, proquestno: NN12455, Theses scanned by UMI/ProQuest. |
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