The testing undertaken for this dissertation is intended to help quantify the various time-dependant deformation processes around typical deep level hard rock tabular excavations. Three mechanisms were investigated and two different hard rock types, Ventersdorp Lava and Elsburg Quartzite were used. Uniaxial compression creep studies were done as the first part of the study followed by shear creep studies on discontinuities where crushed lava and crushed quartzite as well as a natural gouge were used as infilling. An important conclusion made is that the relationship between grain size and infilling thickness is more important than previously might have been assumed. The last part of the study consisted of triaxial post-failure relaxation tests. As far as could be determined, this is the first time triaxial post-failure tests were attempted, particularly on typical South African hard rocks. An important finding of this study is that during compression creep as well as during triaxial post-failure relaxation the amount of energy dissipated for the lava is significantly less than for quartzite. For mines operating at great depth (more than 2000m) the implication is that the rock material might relax much more slowly than might have been assumed and this means that after failure the rock mass continues to store large amounts of strain energy. This study provides the first data available for energy change calculations in fractured rock masses. Three mechanisms of time-dependant deformation were quantified providing valuable data for numerical investigations. / Dissertation (MSc (Mine Strata Control))--University of Pretoria, 2006. / Mining Engineering / unrestricted

Thesis: M.S., Massachusetts Institute of Technology, Department of Mechanical Engineering, 1979 / Bibliography: leaves 204-212. / by Peter Michael Switchenko. / M.S. / M.S. Massachusetts Institute of Technology, Department of Mechanical Engineering

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Civil Engineering, 1982. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING. / Bibliography: leaves 161-168. / by Michael Archangel Semeraro, Jr. / M.S.

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Civil Engineering, 1979. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING. / Bibliography: leaves 201-208. / by William Simon Dershowitz. / M.S.

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.

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.

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.

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.

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.

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.