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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Stability assessment of entry roofs in underlying multiple seam mines /

Akram, Muhammad, January 1993 (has links)
Thesis (Ph. D.)--Virginia Polytechnic Institute and State University, 1993. / Vita. Abstract. Includes bibliographical references (leaves 158-167). Also available via the Internet.
2

Stress analysis in longwall entry roof under high horizontal stress

Chen, Hanjie, January 1999 (has links)
Thesis (Ph. D.)--West Virginia University, 1999. / Title from document title page. Document formatted into pages; contains xvii, 278 p. : ill. (some col.), maps. Vita. Includes abstract. Includes bibliographical references (p. 274-277).
3

An appraisal of the pillar support system at the St. Helena gold mine

Hazell, A. A. 26 January 2015 (has links)
No description available.
4

Classification of paleochannels and their relationship to synsedimentary faulting within the Lower Elkhorn coal zone, Pikeville Formation, Breathitt Group, Southeastern Kentucky

Shultz, Michael Garry. January 2003 (has links) (PDF)
Thesis (M.S.)--University of Kentucky, 2003. / Title from document title page. Document formatted into pages; contains x, 143 p. : ill. Includes abstract. Includes bibliographical references (p. 139-142).
5

Geological mapping of entry roof in mines

Gu, Quanzhong. January 1900 (has links)
Thesis (Ph. D.)--West Virginia University, 2003. / Title from document title page. Document formatted into pages; contains xi, 191 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 137-139).
6

Influence of cutting sequence and time effects on cutters and roof falls in underground coal mine numerical approach /

Ray, Anil Kumar. January 2009 (has links)
Thesis (Ph. D.)--West Virginia University, 2009. / Title from document title page. Document formatted into pages; contains xvi, 285 p. : ill. (some col.), col maps. Includes abstract. Includes bibliographical references (p. 278-285).
7

Longwall weighting events at Phalen Colliery, Nova Scotia, Canada

MacDonald, Robert J. January 1900 (has links)
Thesis (M.S.)--West Virginia University, 2000 / Title from document title page. Document formatted into pages; contains iii, 84 p. : ill. (some col.), maps (some col.). Vita. Includes abstract. Includes bibliographical references (p. 49-50).
8

A geostatistical calculation of the coal mine roof rating

Petrovich, Matthew A. January 1900 (has links)
Thesis (M.S.)--West Virginia University, 2006. / Title from document title page. Document formatted into pages; contains xii, 155 p. : ill. (some col.), map (part col.). Includes abstract. Includes bibliographical references (p. 106-108).
9

Geomechanical and weathering properties of weak roof shales in coal mines

Gurgenli, Hakan. January 2006 (has links)
Thesis (M.S.)--West Virginia University, 2006. / Title from document title page. Document formatted into pages; contains ix, 99 p. : ill. (some col.), maps (part col.). Includes abstract. Includes bibliographical references (p. 77-81).
10

New concepts in tailgate strata behaviour and implications for support design

Tarrant, Gregory Colin, Mining, UNSW January 2006 (has links)
Tailgate stability within longwall coal mining is critical to longwall productivity and safety of mine personnel. A mechanistic model was developed and tested to explain observed high deformation tailgate behaviour characterised by lateral strata movement. Field investigations were conducted at three Australian longwall mines with an emphasis on the measurement of; horizontal strata movement about gateroads during longwall extraction, and the load/deformation characteristics of standing supports. 3D numerical modelling was used to simulate tailgate deformation, and interaction of various support types and design strategies. The sensitivity of strata and support behaviour to; variations in roof geology, strength of sliding interfaces, depth of cover, pre-mining horizontal stress magnitude and orientation, and strength and stiffness characteristics of standing supports was modelled. Laboratory investigations of a standing support product, the ???Can???, at reduced scale (one third) were conducted. The tests determined the loading mechanics of the product and provided a basis for optimisation of the engineering properties (strength and stiffness). Horizontal strata movement about longwall extraction was found to have a significant impact on strata behaviour at two of the three mines investigated. The term ???skew roof??? was coined to describe the deformation process. Essentially the roof strata was found to ???skew??? towards the approaching goaf. The key geotechnical factors found to control the skew roof mechanism were; magnitude and orientation of the pre-mining horizontal stress, presence of weak interfaces along which sliding could occur, and shear strength of the interfaces. Measurement of the nature and extent of skew roof deformation specific to each mine provided a sound engineering basis for support design. These included; the relative roles of long tendons versus standing support, optimal pattern (position across and along the roadway) of standing supports, and appropriate strength and stiffness characteristics. The findings were successfully implemented at Metropolitan Colliery in particular, where adequate tailgate serviceability has been achieved within a high deformation environment, and whilst maintaining a relatively small chain pillar width. The research has achieved an alternative to empirical and trial and error tailgate support design methods.

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