- Email: [email protected]
Elastic properties of jointed rock masses with regard to their rock mass rating value
70A 942073 Research on the effect of gouge thickness on the mechanical properties of joints Li Rongqiang; Chen Hongxin; Kong Defang
classification is re-evaluated considering the influences of intact rock density, joint aperture, and tightness. A simple three part visual classification is proposed based on the current state of knowledge of behaviour of the Chalk.
Proc 26th Annual Conference of the Engineering Group of the Geological Society, The Engineering Geology of Weak Rock, Leeds, 9-13 September 1990 P283-286. Publ Rotterdam: A A Balkema, 1993 (Engineering Geology Special Publication No, 8)
942077 Modelling of jointed rock masses reinforced by rock bolts Sakurai, S; Kawashima, I
Natural and artificial joints of a quartzose phyllite with measured joint surface characteristics were subject to direct shear tests. Different thicknesses (0-6ram) of natural fault gouge were used in the tests. A formula is derived to predict shear strength in terms of mean asperity height, JCS, normal stress, and thickness and friction angle of the gouge. 942074 Advances in the in situ testing of weak mudstone Thompson, R P; Newman, R L; Davis P D
Proc 26th Annual Conference of the Engineering Group of the Geological Society, The Engineering Geology of Weak Rock, Leeds, 9-13 September 1990 P303-310. Publ Rotterdam: A A Balkema, 1993 (Engineering Geology Special Publication No. 8) It is difficult to obtain good quality samples of weak rocks, which may be weathered and fractured, and attention has been paid to field measurement of mass strength and stiffness. Crosshole and downhole geophysics, SPT, high pressure dilatometer, and self-boring pressuremeter methods were applied at a site of Mercia Mudstone (Keuper Marl) rocks. Results are presented and analysed. Stiffness values are compared to those from pile loading tests. A tentative relation between stiffness, strength, and strain level is derived and compared to triaxial test data. 942075 Elastic properties of jointed rock masses with regard to their rock mass rating value Boyd, R D
Proc 26th Annual Conference of the Engineering Group of the Geological Society, The Engineering Geology of Weak Rock, Leeds, 9-13 September 1990 P329-336. Publ Rotterdam: A A Balkema, 1993 (Engineering Geology Special Publication No. S) From consideration of an idealised elastic rock mass model (Kulhawy, 1978) and the CSIR classification, it is suggested that the CSIR rock mass rating system intrinsically evaluates parameters controlling the deformation behaviour. A close correlation between RMR and deformability modulus may be expected. Theoretical and empirical relations are presented which indicate significant stress level dependence for materials with low RMR. A chart is produced showing relations between 5 elastic parameters, from which the remainder can be obtained knowing only one. Typical rock material properties are imposed on this chart. 942076 Assessing the mass compressibility of Chalk from visual description Matthews, M G A; Clayton, C R I; Russel, C S
Proc 26th Annual Conference of the Engineering Group of the Geological Society, The Engineering Geology of Weak Rock, Leeds, 9-13 September 1990 P337-345. Publ Rotterdam: A A Balkema, 1993 (Engineering Geology Special Publication No. 8) Typical load-settlement behaviour of foundations on chalk is assessed, including the initial work at Mundford and recent large-diameter surface plate load tests. The Mundford visual
Proc International Symposium on Rock Support, Sudbury, 1619 June, 1992 P547-550. Publ Rotterdam." A A Balkema, 1992 Continuum mechanics modelling of jointed rock masses reinforced by bolts is difficult, as the stiffness increases following bolting, particularly for hard rocks. Model materials have been used to simulate soft and hard rocks with and without joints and/or bolts. Stress strain curves are illustrated and compared with continuum mechanics simulations. It is suggested that bolted hard rocks should be modelled as a continuum only after bolt installation and that joint-bolt interaction must be taken into account. Soft rocks can be modelled as a continuum body with bolts as beam elements.
Fracture processes See also: 942247, 942265, 942474 942078 Simulating seismoacoustics in a physical rockhurst model (In German) Vasters, J; Asshof, U
Giuckauf-forschungsb V54, N4, Aug 1993, P153-166 In an attempt to improve knowledge of relations between acoustic emission and rockburst, physical model tests were carried out, with coal compressed between two platens whilst seismoacoustic activity was monitored. Event rate in terms of unit time or unit deformation at constant loading rate was seen to correlate only moderately well with stress state in the sample. 942079 Character of coal fracture treatments in Oak Grove Field, Black Warrior Basin Palmer, I D; King, N S; Sparks, D P
In Situ V17, N3, 1993, P273-309 Forty-three fracture treatments using borate crosslinked gelled water and sand proppant in the Mary Lee/Blue Creek and Black Creek seems have been analysed. Two broad categories are observed, unconfined height growth and fractures confined to the seam, with horizontal and vertical components (Tshaped). Conditions under which each type occurs and the resulting gas production performance are discussed. 942080 Fractal fragment size distribution for brittle rocks. Technical note Nagahama, H
Int d Rock Mech Min Sci V30, N4, Aug 1993, P469-471 Fragmentation has been demonstrated to be a scale invariant process. Two new scaling laws on energy-size reduction for fragmentation are presented and the relation between fractaI dimensions for the size distribution and shape (surface roughness) examined.
classification is re-evaluated considering the influences of intact rock density, joint aperture, and tightness. A simple three part visual classification is proposed based on the current state of knowledge of behaviour of the Chalk.
Proc 26th Annual Conference of the Engineering Group of the Geological Society, The Engineering Geology of Weak Rock, Leeds, 9-13 September 1990 P283-286. Publ Rotterdam: A A Balkema, 1993 (Engineering Geology Special Publication No, 8)
942077 Modelling of jointed rock masses reinforced by rock bolts Sakurai, S; Kawashima, I
Natural and artificial joints of a quartzose phyllite with measured joint surface characteristics were subject to direct shear tests. Different thicknesses (0-6ram) of natural fault gouge were used in the tests. A formula is derived to predict shear strength in terms of mean asperity height, JCS, normal stress, and thickness and friction angle of the gouge. 942074 Advances in the in situ testing of weak mudstone Thompson, R P; Newman, R L; Davis P D
Proc 26th Annual Conference of the Engineering Group of the Geological Society, The Engineering Geology of Weak Rock, Leeds, 9-13 September 1990 P303-310. Publ Rotterdam: A A Balkema, 1993 (Engineering Geology Special Publication No. 8) It is difficult to obtain good quality samples of weak rocks, which may be weathered and fractured, and attention has been paid to field measurement of mass strength and stiffness. Crosshole and downhole geophysics, SPT, high pressure dilatometer, and self-boring pressuremeter methods were applied at a site of Mercia Mudstone (Keuper Marl) rocks. Results are presented and analysed. Stiffness values are compared to those from pile loading tests. A tentative relation between stiffness, strength, and strain level is derived and compared to triaxial test data. 942075 Elastic properties of jointed rock masses with regard to their rock mass rating value Boyd, R D
Proc 26th Annual Conference of the Engineering Group of the Geological Society, The Engineering Geology of Weak Rock, Leeds, 9-13 September 1990 P329-336. Publ Rotterdam: A A Balkema, 1993 (Engineering Geology Special Publication No. S) From consideration of an idealised elastic rock mass model (Kulhawy, 1978) and the CSIR classification, it is suggested that the CSIR rock mass rating system intrinsically evaluates parameters controlling the deformation behaviour. A close correlation between RMR and deformability modulus may be expected. Theoretical and empirical relations are presented which indicate significant stress level dependence for materials with low RMR. A chart is produced showing relations between 5 elastic parameters, from which the remainder can be obtained knowing only one. Typical rock material properties are imposed on this chart. 942076 Assessing the mass compressibility of Chalk from visual description Matthews, M G A; Clayton, C R I; Russel, C S
Proc 26th Annual Conference of the Engineering Group of the Geological Society, The Engineering Geology of Weak Rock, Leeds, 9-13 September 1990 P337-345. Publ Rotterdam: A A Balkema, 1993 (Engineering Geology Special Publication No. 8) Typical load-settlement behaviour of foundations on chalk is assessed, including the initial work at Mundford and recent large-diameter surface plate load tests. The Mundford visual
Proc International Symposium on Rock Support, Sudbury, 1619 June, 1992 P547-550. Publ Rotterdam." A A Balkema, 1992 Continuum mechanics modelling of jointed rock masses reinforced by bolts is difficult, as the stiffness increases following bolting, particularly for hard rocks. Model materials have been used to simulate soft and hard rocks with and without joints and/or bolts. Stress strain curves are illustrated and compared with continuum mechanics simulations. It is suggested that bolted hard rocks should be modelled as a continuum only after bolt installation and that joint-bolt interaction must be taken into account. Soft rocks can be modelled as a continuum body with bolts as beam elements.
Fracture processes See also: 942247, 942265, 942474 942078 Simulating seismoacoustics in a physical rockhurst model (In German) Vasters, J; Asshof, U
Giuckauf-forschungsb V54, N4, Aug 1993, P153-166 In an attempt to improve knowledge of relations between acoustic emission and rockburst, physical model tests were carried out, with coal compressed between two platens whilst seismoacoustic activity was monitored. Event rate in terms of unit time or unit deformation at constant loading rate was seen to correlate only moderately well with stress state in the sample. 942079 Character of coal fracture treatments in Oak Grove Field, Black Warrior Basin Palmer, I D; King, N S; Sparks, D P
In Situ V17, N3, 1993, P273-309 Forty-three fracture treatments using borate crosslinked gelled water and sand proppant in the Mary Lee/Blue Creek and Black Creek seems have been analysed. Two broad categories are observed, unconfined height growth and fractures confined to the seam, with horizontal and vertical components (Tshaped). Conditions under which each type occurs and the resulting gas production performance are discussed. 942080 Fractal fragment size distribution for brittle rocks. Technical note Nagahama, H
Int d Rock Mech Min Sci V30, N4, Aug 1993, P469-471 Fragmentation has been demonstrated to be a scale invariant process. Two new scaling laws on energy-size reduction for fragmentation are presented and the relation between fractaI dimensions for the size distribution and shape (surface roughness) examined.