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Fractal estimation of joint roughness coefficients
152A 933101 Measured and calculated closures of open and brine filled shafts and deep vertical boreheles in salt Munson, D E; De Vries, K L; Sehiermeister, D M; De Yonge, W F; Jones, R L Proc 33rd US Symposium on Rock Meclumies, Santa Fe, 3-5 June 1992 1)439-448. Publ Rotterdam: A A Baikema, 1992 Very early time closure data are presented from the Air Intake shaft at the WIPP, which was instrumented during construction. These measured data are compared to numerical calculations using the modified Munson-De Vries constitutive model, which has been used successfully to predict WIPP room closure. The calculations are extended to estimate closure of brine-filled shafts and boreholes. Good agreement was also possible if simple slice mesh models were adopted.
Surface properties 933102 Experimental study on the ani~tmpy and stress-dependency of the strength and ddormnbWtyof rock joints Jing,L; Nordlund, E; Stephansson, O Int J Rock Mech Min Sci II29, N6, Nov 1992, P535-542 Tests on concrete replicas of two natural joints in granite, one previously sheared and slightly weathered, the other fresh and perfectly mated, are described. Shear tests using a servo-controlled hydraulic shear box and tilt tests on a rotational tilt table have been carried out. Anisotropy and stress dependency of strength and deformation properties of the joints have been investigated. Rates of dilatancy and contraction of joint samples during cyclic shear tests are dependent on initial sample surface conditions. Empirical relations to describe these joint properties are proposed and will be used in development of joint constitutive models.
933105 Magnetic resonance relaxation study of preferential wettabWty effects on displacement efficiency in chalk samples Borgia, G C; Fantazzini, P; Fanti, G; Mesini, E Pet Sci Engng V8, N2, Sept 1992, P153-159 Nuclear Magnetic Resonance (NMR) relaxation of water H nuclei has been successfully applied in examination of preferential wettability surface effects on the distribution of oil and water in chalk samples after one liquid has been displaced by the other. Different water and oil configurations are obtained for rocks of different wettability. Valuable information is also obtained on the role played by pore size in the displacement phenomenon.
933106 Experimental study on the relation between fractal dimension and shear strength Wakabayashi, N; Fukushige, I Proc Conference on Fractured and Joimed Rock Masses, Lake Tahoe, 3-5 June 1992 P126-131. Publ California: Lawrence Berkeley Laboratory, 1992 Barton's JRC is widely used to describe joint roughness, but its application requires experience and engineering judgment. As an alternative, a method to quantify joint roughness in terms of fractal dimension is proposed and an equation to evaluate JRC from this is given. Laboratory tests on artificial joints involved determination of joint roughness, evaluation of JRC and fractal dimension, and comparison with shear strength. It is concluded that average roughness of a joint can be quantified in terms of its fractal dimension and that ratio of shear strength to uniaxial compressive strength of a joint is effectively constant for joints of different materials if fractal dimensions are equal.
933103
Dynamic impact abrasion resistance for rocks AI-Ameen, S I; Waller, M D Int J Rock Mech Min Sci V29, N6, Nov 1992, P555-560 Although abrasive wear affects mining machinery, there is no generally accepted test for abrasiveness and little work has been carried out on the softer rocks. The Dynamic Impact Abrasion Index (DIAI) test of Cassati was developed to simulate dynamic abrasive wear by fine particles. A DIAI apparatus is presented in which weight loss of a metal shim in the stream of air-transported, carefully sized abrasive particles is used in assessing abrasiveness. A large number of tests have been carried out on coal measures rocks and good correlation is seen between abrasiveness and hardness and amounts of mineral constituents. 933104
933107 Fractal estimation of joint roughness coefficients Xie, H; Pariseau, W G Proc Conference on Fractured and Jointed Rock Masses, Lake Tahoe, 3-5 June 1992 P132-139. Publ California: Lawrence Berkeley Laboratory, 1992 A procedure for estimating JRC in terms of fractal dimension is presented. Roughness is considered as a fractal structure with finite generations. A generalised fractal model of joint profile is established on the basis of the triadic Koch curve. Fractal dimension is described in terms of base length and average height of the asperities. An empirical relation between D and JRC is proposed. This procedure is simpler to execute than other reported fractal measurement methods for determining JRC.
Design of socketed drilleddrafts in limestone McVay, M C; Townsend, F C; Williams, R C J Geoteeil Fa~ng Di~ ASCE 11118, NIO, Oct 1992, P16261637 Drilled piles socketed into limestone bedrock are usually designed relying on skin friction, assuming only a nominal end bearing load because of uncertainty in spatial variability of the bedrock. Several design methods of estimating rock/shaft friction on the basis of laboratory tests are reviewed. These rely on unconfined compression tests alone or together with split tensile tests. A database of 14 field load tests is used to examine accuracy of predictions of shaft friction. The twoparameter method gives the best results. An alternative method of estimation based on results of pullout tests on grouted anchors is proposed.
933108 Fractal dimension of joint roughness surfaces Muralha, J Proc Conference on Fractured and Joimed Rock Masses, Lake Tahoe, 3-5 June 1992 P211-218. Publ California: Lawrence Berkeley Laboratory, 1992 An introduction to the concept of the fractal dimension and methods for its measurement is presented, and ways in which fractal geometry may be applied to describe joint surfaces and joint profiles are investigated. The ability of fractal geometries replicating natural surfaces to be generated by computers is one advantage in their use to describe rock joints.
© 1993 Pergamon Press Ltd. Reproduction not permitted
Surface properties 933102 Experimental study on the ani~tmpy and stress-dependency of the strength and ddormnbWtyof rock joints Jing,L; Nordlund, E; Stephansson, O Int J Rock Mech Min Sci II29, N6, Nov 1992, P535-542 Tests on concrete replicas of two natural joints in granite, one previously sheared and slightly weathered, the other fresh and perfectly mated, are described. Shear tests using a servo-controlled hydraulic shear box and tilt tests on a rotational tilt table have been carried out. Anisotropy and stress dependency of strength and deformation properties of the joints have been investigated. Rates of dilatancy and contraction of joint samples during cyclic shear tests are dependent on initial sample surface conditions. Empirical relations to describe these joint properties are proposed and will be used in development of joint constitutive models.
933105 Magnetic resonance relaxation study of preferential wettabWty effects on displacement efficiency in chalk samples Borgia, G C; Fantazzini, P; Fanti, G; Mesini, E Pet Sci Engng V8, N2, Sept 1992, P153-159 Nuclear Magnetic Resonance (NMR) relaxation of water H nuclei has been successfully applied in examination of preferential wettability surface effects on the distribution of oil and water in chalk samples after one liquid has been displaced by the other. Different water and oil configurations are obtained for rocks of different wettability. Valuable information is also obtained on the role played by pore size in the displacement phenomenon.
933106 Experimental study on the relation between fractal dimension and shear strength Wakabayashi, N; Fukushige, I Proc Conference on Fractured and Joimed Rock Masses, Lake Tahoe, 3-5 June 1992 P126-131. Publ California: Lawrence Berkeley Laboratory, 1992 Barton's JRC is widely used to describe joint roughness, but its application requires experience and engineering judgment. As an alternative, a method to quantify joint roughness in terms of fractal dimension is proposed and an equation to evaluate JRC from this is given. Laboratory tests on artificial joints involved determination of joint roughness, evaluation of JRC and fractal dimension, and comparison with shear strength. It is concluded that average roughness of a joint can be quantified in terms of its fractal dimension and that ratio of shear strength to uniaxial compressive strength of a joint is effectively constant for joints of different materials if fractal dimensions are equal.
933103
Dynamic impact abrasion resistance for rocks AI-Ameen, S I; Waller, M D Int J Rock Mech Min Sci V29, N6, Nov 1992, P555-560 Although abrasive wear affects mining machinery, there is no generally accepted test for abrasiveness and little work has been carried out on the softer rocks. The Dynamic Impact Abrasion Index (DIAI) test of Cassati was developed to simulate dynamic abrasive wear by fine particles. A DIAI apparatus is presented in which weight loss of a metal shim in the stream of air-transported, carefully sized abrasive particles is used in assessing abrasiveness. A large number of tests have been carried out on coal measures rocks and good correlation is seen between abrasiveness and hardness and amounts of mineral constituents. 933104
933107 Fractal estimation of joint roughness coefficients Xie, H; Pariseau, W G Proc Conference on Fractured and Jointed Rock Masses, Lake Tahoe, 3-5 June 1992 P132-139. Publ California: Lawrence Berkeley Laboratory, 1992 A procedure for estimating JRC in terms of fractal dimension is presented. Roughness is considered as a fractal structure with finite generations. A generalised fractal model of joint profile is established on the basis of the triadic Koch curve. Fractal dimension is described in terms of base length and average height of the asperities. An empirical relation between D and JRC is proposed. This procedure is simpler to execute than other reported fractal measurement methods for determining JRC.
Design of socketed drilleddrafts in limestone McVay, M C; Townsend, F C; Williams, R C J Geoteeil Fa~ng Di~ ASCE 11118, NIO, Oct 1992, P16261637 Drilled piles socketed into limestone bedrock are usually designed relying on skin friction, assuming only a nominal end bearing load because of uncertainty in spatial variability of the bedrock. Several design methods of estimating rock/shaft friction on the basis of laboratory tests are reviewed. These rely on unconfined compression tests alone or together with split tensile tests. A database of 14 field load tests is used to examine accuracy of predictions of shaft friction. The twoparameter method gives the best results. An alternative method of estimation based on results of pullout tests on grouted anchors is proposed.
933108 Fractal dimension of joint roughness surfaces Muralha, J Proc Conference on Fractured and Joimed Rock Masses, Lake Tahoe, 3-5 June 1992 P211-218. Publ California: Lawrence Berkeley Laboratory, 1992 An introduction to the concept of the fractal dimension and methods for its measurement is presented, and ways in which fractal geometry may be applied to describe joint surfaces and joint profiles are investigated. The ability of fractal geometries replicating natural surfaces to be generated by computers is one advantage in their use to describe rock joints.
© 1993 Pergamon Press Ltd. Reproduction not permitted