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Sprayed lining in fissured ground (In French)
102A
Shotcrete 912312 Automated ground support systems in deep metal mines shotcrete Hoskins, J R Proc 7th Annual Workshop Generic Mineral Technology Center Mine Systems Design and Ground Control, Biacksburg, 22-24 October 1989 P161-165. Publ Blacksburg: Virginia Polytechnic Institute and State Unit'ersity, 1989 Shotcreting has been chosen as a support method for automation due to the possibility of remote continuous placement and ability to be varied to meet structural needs. There is also the possibility of placement during formation of a shaft by reaming of a previously drilled blind hole. Details of this support system and further studies on stress concentrations around a circular opening in which local strata orientations create points of non-uniform loading are discussed.
912316 Development of new yielding type of supports for iongwall gate-roads Ghosh, C N J Min Metal Fuels V38, N4/5, April/May 1990, P84-88 Maintenance of gate roads is very important in Iongwall mining with caving. At the Moonidih colliery in India, the 4.8m wide by 2.5m gateroad was supported by grouted bolts and yielding type steel props using l-section joists and hollow casing. This proved insufficient. Roof strata and support behaviour and loads were monitored to determine design specifications for improved support. U-section yielding props of the material usually employed for yielding arches were developed in the laboratory. Initial field tests indicate their suitability.
Grouting See also: 912066, 912156
912313 Sprayed lining in fissured ground (In French) Fine, J; Liu, A lndustrie Mineraie V72, Aug-Sept 1990. P59-61
912317 New technique for grouting old mine workings Kipko, E J; Kipko, A E Min Sci Tecimoi VII, N2, Sept 1990, P199.206
Shotcrete and gunite are established support materials, most commonly used in difficult ground to protect against time dependent and progressive failure. A laboratory program to demonstrate the suitability of shotcrete to support excavations in hard fissured rocks, to prevent detachment of rock blocks, is presented. The versatility of the material is first shown using tests to measure the resistance of shotcrete to shear or debonding failure. Simulation of support of a gallery in heavily jointed rock is used to illustrate the suitability of shotcrete alone for such structures.
Grouting techniques have developed in response to need to ensure safety against impact of abandoned mine workings. Methods of job planning, tools and instrumentation, and improved grout mixtures and their properties are described. Case histories of their application are presented.
Direct rock support methods 912314 Nonlinear finite-element-method model for calculating yielding arch supports in eoalmining (In German) Beckmann, D; Klein, J; Weise, A Giuckauf-forschangsh V51. N4, Aug 1990. P179-183 Yielding arch supports are widely used to withstand large strata movements in coal mines. A PC based nonlinear FEM model has been designed to minimise the number of full scale tests necessary in yielding arch development. Geometrical nonlinearity to allow large displacements, nonlinear bedding of support base units, and nonlinearity of the behaviour of the sliding components are included. Design philosophy is explained, and results of its application illustrated.
912315 Fuzzy evaluation of powered support suitability to coal seams Guo Wenzhang; Xin Jingmin lnt d Min Geol Engng V8, N2. June 1990, P163-177 Powered support specification should take into account roof formation, seam thickness and gradient, seam floor conditions, and geological discontinuities. Adequate data on these are not generally available, and subjective judgement must be used. To make this unnecessary, a fuzzy multicriteria decisionmaking model is proposed to transform non-quantitative judgements into quantitative ones, which may be processed by computer. A detailed example of its application is presented.
912318 Ring of success Martin, D Tunn Tunnig V22, N9, Sept 1990. P42-44 A forepoling method for providing roof support in soft ground tunnelling is presented. Sub-horizontal holes are first drilled using the Tubex method. This uses an eccentric drill inside a steel tube, such that when the drill is withdrawn through the tube, an annulus remains bet~een tube and borehole walls. The tubes are filled with grout under pressure, which causes valves in the tube wall to burst, and pressurised grout escapes through the perforation into the surrounding formation. The technique is economic and practical. Examples of its use are presented.
Reinforced earth See also: 912329. 912389 912319 Modelling of the failure of sands reinforced with fibres: micromechanlcul approach to the inclusion/matrix interaction (In French) Delyon, F; Levy, Y E; Dufresne, D Bull Liaison Labs Ponts Clmussees N167. May-June 1990, P53-60 Results of studies on fibre reinforced granular materials, such as Texsol,are presented. Failure, in particular failure at the soil/inclusion interface, was investigated. Forces at this interface are regarded as frictional. The main aim of this work was to understand the nature of these forces. A model is developed for soil-inclusion interaction. It is used to evaluate cohesion of the reinforced soil mass and mean intergranular forces under anisotropic loading. Pullout tests on single fibres and an analytical approach using the MUDEC program are used to substantiate the findings.
© 1991 Pergamon Press plc. Reproduction not permitted
Shotcrete 912312 Automated ground support systems in deep metal mines shotcrete Hoskins, J R Proc 7th Annual Workshop Generic Mineral Technology Center Mine Systems Design and Ground Control, Biacksburg, 22-24 October 1989 P161-165. Publ Blacksburg: Virginia Polytechnic Institute and State Unit'ersity, 1989 Shotcreting has been chosen as a support method for automation due to the possibility of remote continuous placement and ability to be varied to meet structural needs. There is also the possibility of placement during formation of a shaft by reaming of a previously drilled blind hole. Details of this support system and further studies on stress concentrations around a circular opening in which local strata orientations create points of non-uniform loading are discussed.
912316 Development of new yielding type of supports for iongwall gate-roads Ghosh, C N J Min Metal Fuels V38, N4/5, April/May 1990, P84-88 Maintenance of gate roads is very important in Iongwall mining with caving. At the Moonidih colliery in India, the 4.8m wide by 2.5m gateroad was supported by grouted bolts and yielding type steel props using l-section joists and hollow casing. This proved insufficient. Roof strata and support behaviour and loads were monitored to determine design specifications for improved support. U-section yielding props of the material usually employed for yielding arches were developed in the laboratory. Initial field tests indicate their suitability.
Grouting See also: 912066, 912156
912313 Sprayed lining in fissured ground (In French) Fine, J; Liu, A lndustrie Mineraie V72, Aug-Sept 1990. P59-61
912317 New technique for grouting old mine workings Kipko, E J; Kipko, A E Min Sci Tecimoi VII, N2, Sept 1990, P199.206
Shotcrete and gunite are established support materials, most commonly used in difficult ground to protect against time dependent and progressive failure. A laboratory program to demonstrate the suitability of shotcrete to support excavations in hard fissured rocks, to prevent detachment of rock blocks, is presented. The versatility of the material is first shown using tests to measure the resistance of shotcrete to shear or debonding failure. Simulation of support of a gallery in heavily jointed rock is used to illustrate the suitability of shotcrete alone for such structures.
Grouting techniques have developed in response to need to ensure safety against impact of abandoned mine workings. Methods of job planning, tools and instrumentation, and improved grout mixtures and their properties are described. Case histories of their application are presented.
Direct rock support methods 912314 Nonlinear finite-element-method model for calculating yielding arch supports in eoalmining (In German) Beckmann, D; Klein, J; Weise, A Giuckauf-forschangsh V51. N4, Aug 1990. P179-183 Yielding arch supports are widely used to withstand large strata movements in coal mines. A PC based nonlinear FEM model has been designed to minimise the number of full scale tests necessary in yielding arch development. Geometrical nonlinearity to allow large displacements, nonlinear bedding of support base units, and nonlinearity of the behaviour of the sliding components are included. Design philosophy is explained, and results of its application illustrated.
912315 Fuzzy evaluation of powered support suitability to coal seams Guo Wenzhang; Xin Jingmin lnt d Min Geol Engng V8, N2. June 1990, P163-177 Powered support specification should take into account roof formation, seam thickness and gradient, seam floor conditions, and geological discontinuities. Adequate data on these are not generally available, and subjective judgement must be used. To make this unnecessary, a fuzzy multicriteria decisionmaking model is proposed to transform non-quantitative judgements into quantitative ones, which may be processed by computer. A detailed example of its application is presented.
912318 Ring of success Martin, D Tunn Tunnig V22, N9, Sept 1990. P42-44 A forepoling method for providing roof support in soft ground tunnelling is presented. Sub-horizontal holes are first drilled using the Tubex method. This uses an eccentric drill inside a steel tube, such that when the drill is withdrawn through the tube, an annulus remains bet~een tube and borehole walls. The tubes are filled with grout under pressure, which causes valves in the tube wall to burst, and pressurised grout escapes through the perforation into the surrounding formation. The technique is economic and practical. Examples of its use are presented.
Reinforced earth See also: 912329. 912389 912319 Modelling of the failure of sands reinforced with fibres: micromechanlcul approach to the inclusion/matrix interaction (In French) Delyon, F; Levy, Y E; Dufresne, D Bull Liaison Labs Ponts Clmussees N167. May-June 1990, P53-60 Results of studies on fibre reinforced granular materials, such as Texsol,are presented. Failure, in particular failure at the soil/inclusion interface, was investigated. Forces at this interface are regarded as frictional. The main aim of this work was to understand the nature of these forces. A model is developed for soil-inclusion interaction. It is used to evaluate cohesion of the reinforced soil mass and mean intergranular forces under anisotropic loading. Pullout tests on single fibres and an analytical approach using the MUDEC program are used to substantiate the findings.
© 1991 Pergamon Press plc. Reproduction not permitted