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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.
191

Design approaches for grouting of rock fractures; Theory and practice

Yaghoobi Rafi, Jalaleddin January 2013 (has links)
Currently, cement base grout is used widely for sealing of the rock fractures in order to decrease the permeability of rock mass. Grouting procedure is one of the main tasks in cycle of rock excavation. In addition, huge amount of grout should be used during dam construction in order to seal the bedding and embankment walls. Therefore, considering the effect of grouting in duration and cost of the project, improving the design methods seems essential. In successful grouting the goal is to achieve the required sealing of fractures while avoiding ground movement due to applied pressure. Empirical methods have been developed to decide the pumping pressure, grout mix properties and stop criteria in order to fulfill requirements of successful grouting but there are ambiguities in using them and performance of them have been questioned. In these methods, assumptions and criteria are based on rules of thumbs and experiences from previous projects. The main uncertainties connected to these methods are identifying amount of grout spread and state of the fracture. Theoretical approach is an analytical solution which provides the chance for estimation of penetration length of the grout in real time. Furthermore, void filling fracture aperture and trend of the grout flow are estimated. As the development of this theory, elastic and ultimate jacking limits have been established based on the estimated penetration length. Therefore, it is possible to identify jacking of the fracture and estimate the state of the fracture in real time.  In this research work, performance of this theoretical approach which is called “Real Time Grouting Control Method” has been validated through case studies. Properties of the used material, data for pressure and flow in addition to geological characteristics have been gathered from projects in sedimentary rock (Gotvand Dam in Iran and THX Dam in Laos) and hard rock (City Line Project in Sweden). This theory made it possible to observe overflow of grout and jacking of the fractures in sedimentary rock. In place of hard rock with mostly vertical fractures, this theoretical approach confirms usage of higher pressure which will shorten the grouting time. In this research work, variation in properties of the grout mix during grouting has been neglected. moreover, orientation of the fracture and its deformation due to injection pressure are not considered. Despite these assumptions, the results were promising and performance this approach in estimation of grout spread and identifying jacking of the fracture has been verified. / <p>QC 20130520</p> / Rafi, J, Stille, H, Bagheri, M, 2012. Applying “Real Time Grouting Control Method” in Sedimentary Rock, in 4th International Conference on Grouting and Deep Mixing. 16-18 February, New Orleans-USA. / Rafi J, Stille H, 2013. Controlling jacking of rock considering spread of grout and grouting pressure, Accepted in Journal of Tunneling and Underground Space Technology. / Rafi J, Tsuji M, Stille H, 2013. Theoretical Approaches in Grouting Fractures of the Rock Mass: Theories and Applications. Accepted in the 47th US Rock Mechanics / Geomechanics Symposium. 23-26 June, San Francisco, CA, USA. / Rafi J, Tsuji M, Stille H, 2013. Theoretical approaches in grouting design: estimation of penetration length and fracture deformation in real time in Bergmekanikdagen, 11 March, Stockholm-Sweden.
192

An interpretation of field stresses adjacent to selected Canadian mines.

Tan, Bee-koon. January 1971 (has links)
No description available.
193

Field and laboratory studies of the mechanics of faulting

Jones, Lucile Merrill January 1981 (has links)
Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Earth and Planetary Sciences, 1981. / Microfiche copy available in Archives and Science. / Vita. / Bibliography: leaves 91-93. / by Lucile Merrill Jones. / Ph.D.
194

Seismological investigation of the mechanical properties of a hot dry rock geothermal system

Fehler, Michael Clair January 1979 (has links)
Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Earth and Planetary Sciences, 1979. / Microfiche copy available in Archives and Science. / Vita. / Bibliography: leaves 316-327. / by Michael Fehler. / Ph.D.
195

Characterization of stress-induced cracks in rocks

Feves, Michael Lawrence January 1977 (has links)
Thesis. 1977. Ph.D.--Massachusetts Institute of Technology. Dept. of Earth and Planetary Sciences. / Microfiche copy available in Archives and Science. / Vita. / Bibliography : leaves 110-122. / by Michael L. Feves. / Ph.D.
196

Post-failure behavior of westerly granite at elevated temperatures

Wong, Teng-fong January 1981 (has links)
Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Earth and Planetary Sciences, 1981. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND LINDGREN. / Vita. / Bibliography: leaves 164-168. / by Teng-Fong Wong. / Ph.D.
197

Seismic velocities in porous rocks : direct and inverse problems/

Cheng, Chuen Hon Arthur January 1978 (has links)
Thesis. 1978. Sc.D.--Massachusetts Institute of Technology. Dept. of Earth and Planetary Science. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND LINDGREN. / Vita. / Bibliography: leaves 212-219. / by Cheng, Chuen Hon Arthur. / Sc.D.
198

The attenuation of seismic waves in dry and saturated rocks

Johnston, David Hervey January 1979 (has links)
Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Earth and Planetary Sciences, 1979. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND LINDGREN. / Vita. / Bibliography: leaves 378-399. / by David H. Johnston. / Ph.D.
199

Literature review of rock properties for analysis of navigation structures founded on rock

Benson, Carl Philip 15 November 2013 (has links)
A review of behavioral rock properties used for input to the finite element method are summarized. Rock properties presented in the literature were primarily obtained from laboratory specimens. Methods to determine applicable field properties via testing, calculations and empirical correlations are included. Suggested behavioral properties of the structural concrete-to-rock interface are proposed. Specific property values, resulting from the literature review, are presented as input for a finite element parametric evaluation of navigation structures. / Master of Science
200

Layout design for interactive zones in longwall multiple seam mining

Forrest, Peter 21 July 2010 (has links)
Appalachia requires design guidelines for the increasingly popular multi-seam longwall method. Entry layouts often depart from the ideal when finally developed. The thesis examines the occurrence of ground control problems, and possibilities for improvements in strata control, in a variety of undermining situations. The effects of upper seam loading on undermining operations are invest~gated using physical modelling. Photoelastic stress analysis is used as a powerful research tool to analyze complex multiple seam entry systems. Yield pillar use is also examined, in anticipation of their widespread application for ground control. Case examples support the research findings, and specific conclusions aim to assist layout design in interactive zones. / Master of Science

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