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Design analysis of multiple parallel caverns using explicit finite difference methods
97A
Proc 6th International Conference on Rock Mechanics, Montreal, 30 Aug-lO Sept 1987 V2, P1039-1042. Publ Rotterdam: A A Balkema. 1987
892373 Design analysis of multiple parallel caverns using explicit finite difference methods Johansson, E; Riekkola, R; Lorig, L Key Questions in Rock Mechanics: Proc 29th US Symposium, Minneapolis, 13-15 June 1988 P325-333. Publ Rotterdam: A A Balkema, 1988
A damage mechanics theory for a jointed rock mass is proposed, and applied to excavation problems for 3 cavern shapes, conventional mushroom,horse-shoe and bullet. The damage tensor, a second order symmetric tensor to characterise distributed joints in the rock mass, is evaluated from 3D photographic surveying, and results compared with those derived from conventional finite element analysis. Influences of distributed joints on mechanical behaviour of each cavern shape are discussed.
Multiple shallow parallel caverns are required for a wastewater treatment plant in Finland. Effects of local topography, stress fields, gravity, fracturing and weathering, and support must be taken into account. The use of two dimensional explicit finite difference codes in the design procedure is illustrated. Where joint spacing is large relative to problem dimensions, a distinct element code is employed. A continuum code with a Mohr Coulomb no-tension constitutive relation is used where jointing is more generally expressed.
892370 Measurement of rock displacements and its interpretation for the determination of a relaxed zone around a tunnel in a coal mine Lee, K W; Kim, H Y; Lee, H K
892374 Effects of soft floor interaction on room-and-pillar mining -a progress report Caudle, R D; Chugh, Y P; Albarracin, H; Chandrashekhar, K; Liang, C Proc 5th Annual Workshop Generic Mineral Technology Center Mine Systems Design and Ground Control, Tuscaloosa, 26-27 Oct 1987 P23-34. Publ Blacksburg: Virginia Polytechnic and State University, 1987
892369 Deformation and fracturing process of discontinuous rock masses and damage mechanics Kyoya, T; lchikawa, Y; Kawamoto, T
Proc 6th International Conference on Rock Mechanics, Montreal, 30 Aug-lO Sept 1987 V2, P1047-1050. Publ Rotterdam: A A Balkema. 1987 Extensometers were used to monitor displacement and convergence in a tunnel. The size of the relaxed zone was calculated by stress analysis using the boundary element method, considering only isotropic and elastic properties of the rock. Computer predictions did not correlate well with measured values as plastic deformation was not considered. 89237 I Geomechanical criteria of prediction and technology of prevention of rock bursts during excavation in tectonically stressed rocks Markov, G A; Vorobiev, A N; Uralov, V S Proc 6th International Conference on Rock Mechanics, Montreal, 30 Aug-lO Sept 1987 V2, PIIOI-II04. Publ Rotterdam: A A Balkema, 1987 A mathematical model of the description of gravitational tectonic stresses is first presented. The results of long term observations of failure of structures in tectonically stressed rock masses are then described. The influence of the ratio of sum of the tangential and longitudinal effective stresses to compressive strength is illustrated. Failure prevention methods, including alignment of structures at the most favourable orientation of tectonic stress, design and construction methods taking account of tectonic stress, and support measures are considered. 892372 Rock bursting and related phenomena in some Swedish water tunnels Martna, J; Hansen, L Proc 6th International Conference on Rock Mechanics, Montreal, 30 Aug-lO Sept 1987 V2, PI I05-1110. Publ Rotterdam: A A Balkema, 1987 Unstable rock is sometimes encountered in tunnelling and manifests itself as rock burst, slabbing, fracturing, or rock noise. These regions are associated with high tectonic stresses, which cannot be accounted for simply by overburden thickness. Stress induced phenomena arrive or disappear abruptly without obvious reason and cannot be predicted without comprehensive stress measurement. Measured stress fields may change magnitude or direction adjacent to faults. Case studies are presented, and remedial support measures and preventative design methods considered.
Finite element analysis using the A D I N A code was carried out to examine stress distribution around an opening in a room and pillar coal mine with weak floor strata. Strength-deformation properties of the clayshale, mudshale, mudstone, and cIaystone floor rocks were determined in the laboratory. The effects of variation in weak floor thickness, increase in lateral pressure, and increase in opening width on pillar settlement and strata movement were analysed. Nonlinear floor behaviour must be taken into account if predictions are to agree with field measurements. 892375 Lower seam interaction during Iongwall mining Forrest, P; Haycocks, C; Zhou, Y; Wu, W Proc 5th Annual Workshop Generic Mineral Technology Center Mine Systems Design and Ground Control, Tuscaloosa, 26-27 Oct 1987 P35-45. Publ Blacksburg: Virginia Polytechnic and State University, 1987 Mining under existing workings (passive) or being mined over (active) may increase or decrease stress fields around the lower seam. Severity of damage to the lower seam is highly dependent on remnant structures in the upper seam. Ground control problems can occur under rigid pillars, yield pillars, and fibs, each having different effects due to different loading characteristics at the upper seam level. Stress distributions under these loadings have been derived analytically. Effect of yield and rib pillars on load transfer have been studied using photoelastic models. 892376 Interpretation of stress measurements around mining cavities in rock salt - a finite element study Heusermann, S Proc ECONMIG 86, Stuttgart, 16-18 Sept 1986 112, 12P. Publ Stuttgart: Unit'ersity of Stuttgart, 1986 The finite element code A D I N A was used to model stress measurement by overcoring in rock salt, with influences of viscoplastic and elastic properties of the rock included. Stress distribution around multiple drifts and pillars was also modelled. Field measurements are also reported. The analysis allows peculiar stress relief deformation behaviour observed in
:© 1989 Pergamon Press plc. Reproduction not permitted
Proc 6th International Conference on Rock Mechanics, Montreal, 30 Aug-lO Sept 1987 V2, P1039-1042. Publ Rotterdam: A A Balkema. 1987
892373 Design analysis of multiple parallel caverns using explicit finite difference methods Johansson, E; Riekkola, R; Lorig, L Key Questions in Rock Mechanics: Proc 29th US Symposium, Minneapolis, 13-15 June 1988 P325-333. Publ Rotterdam: A A Balkema, 1988
A damage mechanics theory for a jointed rock mass is proposed, and applied to excavation problems for 3 cavern shapes, conventional mushroom,horse-shoe and bullet. The damage tensor, a second order symmetric tensor to characterise distributed joints in the rock mass, is evaluated from 3D photographic surveying, and results compared with those derived from conventional finite element analysis. Influences of distributed joints on mechanical behaviour of each cavern shape are discussed.
Multiple shallow parallel caverns are required for a wastewater treatment plant in Finland. Effects of local topography, stress fields, gravity, fracturing and weathering, and support must be taken into account. The use of two dimensional explicit finite difference codes in the design procedure is illustrated. Where joint spacing is large relative to problem dimensions, a distinct element code is employed. A continuum code with a Mohr Coulomb no-tension constitutive relation is used where jointing is more generally expressed.
892370 Measurement of rock displacements and its interpretation for the determination of a relaxed zone around a tunnel in a coal mine Lee, K W; Kim, H Y; Lee, H K
892374 Effects of soft floor interaction on room-and-pillar mining -a progress report Caudle, R D; Chugh, Y P; Albarracin, H; Chandrashekhar, K; Liang, C Proc 5th Annual Workshop Generic Mineral Technology Center Mine Systems Design and Ground Control, Tuscaloosa, 26-27 Oct 1987 P23-34. Publ Blacksburg: Virginia Polytechnic and State University, 1987
892369 Deformation and fracturing process of discontinuous rock masses and damage mechanics Kyoya, T; lchikawa, Y; Kawamoto, T
Proc 6th International Conference on Rock Mechanics, Montreal, 30 Aug-lO Sept 1987 V2, P1047-1050. Publ Rotterdam: A A Balkema. 1987 Extensometers were used to monitor displacement and convergence in a tunnel. The size of the relaxed zone was calculated by stress analysis using the boundary element method, considering only isotropic and elastic properties of the rock. Computer predictions did not correlate well with measured values as plastic deformation was not considered. 89237 I Geomechanical criteria of prediction and technology of prevention of rock bursts during excavation in tectonically stressed rocks Markov, G A; Vorobiev, A N; Uralov, V S Proc 6th International Conference on Rock Mechanics, Montreal, 30 Aug-lO Sept 1987 V2, PIIOI-II04. Publ Rotterdam: A A Balkema, 1987 A mathematical model of the description of gravitational tectonic stresses is first presented. The results of long term observations of failure of structures in tectonically stressed rock masses are then described. The influence of the ratio of sum of the tangential and longitudinal effective stresses to compressive strength is illustrated. Failure prevention methods, including alignment of structures at the most favourable orientation of tectonic stress, design and construction methods taking account of tectonic stress, and support measures are considered. 892372 Rock bursting and related phenomena in some Swedish water tunnels Martna, J; Hansen, L Proc 6th International Conference on Rock Mechanics, Montreal, 30 Aug-lO Sept 1987 V2, PI I05-1110. Publ Rotterdam: A A Balkema, 1987 Unstable rock is sometimes encountered in tunnelling and manifests itself as rock burst, slabbing, fracturing, or rock noise. These regions are associated with high tectonic stresses, which cannot be accounted for simply by overburden thickness. Stress induced phenomena arrive or disappear abruptly without obvious reason and cannot be predicted without comprehensive stress measurement. Measured stress fields may change magnitude or direction adjacent to faults. Case studies are presented, and remedial support measures and preventative design methods considered.
Finite element analysis using the A D I N A code was carried out to examine stress distribution around an opening in a room and pillar coal mine with weak floor strata. Strength-deformation properties of the clayshale, mudshale, mudstone, and cIaystone floor rocks were determined in the laboratory. The effects of variation in weak floor thickness, increase in lateral pressure, and increase in opening width on pillar settlement and strata movement were analysed. Nonlinear floor behaviour must be taken into account if predictions are to agree with field measurements. 892375 Lower seam interaction during Iongwall mining Forrest, P; Haycocks, C; Zhou, Y; Wu, W Proc 5th Annual Workshop Generic Mineral Technology Center Mine Systems Design and Ground Control, Tuscaloosa, 26-27 Oct 1987 P35-45. Publ Blacksburg: Virginia Polytechnic and State University, 1987 Mining under existing workings (passive) or being mined over (active) may increase or decrease stress fields around the lower seam. Severity of damage to the lower seam is highly dependent on remnant structures in the upper seam. Ground control problems can occur under rigid pillars, yield pillars, and fibs, each having different effects due to different loading characteristics at the upper seam level. Stress distributions under these loadings have been derived analytically. Effect of yield and rib pillars on load transfer have been studied using photoelastic models. 892376 Interpretation of stress measurements around mining cavities in rock salt - a finite element study Heusermann, S Proc ECONMIG 86, Stuttgart, 16-18 Sept 1986 112, 12P. Publ Stuttgart: Unit'ersity of Stuttgart, 1986 The finite element code A D I N A was used to model stress measurement by overcoring in rock salt, with influences of viscoplastic and elastic properties of the rock included. Stress distribution around multiple drifts and pillars was also modelled. Field measurements are also reported. The analysis allows peculiar stress relief deformation behaviour observed in
:© 1989 Pergamon Press plc. Reproduction not permitted