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Keynote lecture: rock stress, structure and mine design
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parameters, and energy distribution are described. Comparisons between the monitoring methods for understanding and forecasting rockburst are attempted. 924506 Keynote lecture: rock stress, structure and mine design Brady, B H G Pro¢ 2nd International Symposium on Rockbursts and Seismicity in Mines, Minneapolis, 8-10 June 1988 P311-321. Pubi Rotterdam: A A Balkema, 1990 The mechanics of rock mass deformation leading to transient instability are considered briefly, and techniques for numerical simulation and analysis of various modes of instability are discussed. Three computational schemes are considered: boundary elements, large-strain finite difference methods for elasto-plastic analysis, and distinct elements for analysis of true discontinuum behaviour. Some applications of these methods in mine excavation design are described, in identifying burst-prone conditions in a rockmass and in developing excavation layouts and sequences to alleviate the hazard of rockbursts. Finally, an analysis is presented which suggests hydraulic injection of slip-prone features may be applicable in mine stress control and rockburst hazard mitigation. 924509 Case studies on large rockbursts in South African gold mines Brummer, R K; Rorke, A J Proc 2nd International Symposium on Roekbursts and Seismicity in Mines, Minneapolis, 8-10 June 1988 P323-329. Publ Rotterdam: A A Balkema, 1990 Rockburst in South African gold mines can be classified into three categories on the basis of underlying mechanism: crush type, pillar foundation failure, and shear slip. The last mechanism, which is responsible for most of the largest events, is examined in detail with several large rockbursts described. By analysing mining layout, outburst, and post failure phenomena it is hoped to develop guidelines to help predict the location and extent of rockburst. 924510 Excess shear stress (ESS) - a case study Holmes, R D; Reeson, J A Proc 2nd International Symposium on Rockbursts and Seismicity in Mines, Minneapolis, 8-10 June 1988 P331-336. Publ Rotterdam: A A Balkema, 1990
Flanagan Fault, sheared by only 1.2mm. Two dimensional boundary element (BITEMJ) and three dimensional coupled boundary element-finite element (BEFE) modelling was used to study the event. Stress and ground movement have been monitored during subsequent mining. Position and orientation of the Beta Fault with respect to stope geometry are critical to initiation of shearing. Shear displacement depends on external loading and fault strength. 924512 Peak particle velocity for rock bursts in some Ontario mines Hedley, D G F Proc 2nd International Symposium on Rockbursts and Seismlcity in Mines, Minneapolis, 8-10 June 1988 P345-348. Publ Rotterdam: A A Balkema, 1990 Peak particle velocities were recorded during 25 rockbursts at the Creighton Mine in Sudbury and the Quirke and Denison Mines at Elliot Lake. Relations between ppv, distance from source, and magnitude of rockburst are examined in terms of conventional seismological and blasting equation formats. Best fit is found with a version of the blasting equation. Measured velocities are significantly lower than those from South African mines under similar conditions, which can be accounted for by greater attenuation of the seismic signals in the more fractured rock masses of Ontario. 924513 Results of prediction of seismic events in the territory of the Bohemian massif Buben, J; Rudajev, V Rock Mechanics as a Multidisciplinary Science: Proc 32nd US Symposium, Norman, 10-12 July 1991 P451-460. Publ Rotterdam: A A Balkema, 1991 Rockburst is a hazard in underground mines of all types in Czechoslovakia's Bohemian massif. Prediction of daily cumulative seismic energy and number of microseisms on the basis of simply measured mine parameters is attempted. Wiener extrapolation, adaptive filtration, and Bayesian (autoregressive) statistical techniques all produce similar results. 924514 Examination of energy calculations applied to coal bump prediction Heasley, K A Rock Mechanics as a Multidisciplinary Science: Proc 32nd US Symposium, Norman, 10-12 July 1991 P481-490. Publ Rotterdam: A A Balkema, 1991
Three of the four shafts of the Buffelsfontein Mine in Western Transvaal experience relatively high levels of seismicity. Following a magnitude 4.3 event in 1987 on Orangia Shaft, an investigation into the state of ESS on major strike oriented faults in the area was undertaken. The mining sequence from 1977-1987 was modelled using the computer program MINSIM D phase 3. 34 events of magnitude greater than 3 which occurred in the area of study in this period were examined to establish relations between physical parameters and ESS. Definite correlations are seen between length of fault exposed by mining, area mined, and seismic moment.
Pillar recovery in deep coal mines with competent roof and floor rock can lead to development of stress concentration and strain energy buildup, culminating in coal bumps. Although energy release rate methods have been used to indicate burst potential in hard rock mines, they have rarely been applied to coal mines. They are used with the displacement discontinuity code MULSIM/NL and field data in numerical simulation of underground coal mine behaviour. Suitability of different values of energy release for predicting coal bumps is examined.
924511 Interaction of slopes, stresses and geologic structure at Mount Charlotte Mine, Western Australia Lee, M F; Beer, G; Windsor, C R Proc 2nd International Symposium on Rockbursts and Sei;micity in Mines, Minneapolis, 8-10 June 1988 P337-343. Publ Rotterdam: A A Balkema, 1990
924515 New approaches to studying rock burst-associated seismicity in mines Coughlin, J; Kranz, R Rock Mechanics as a Multidisciplinary Science: Proc 32nd US Symposium, Norman, 10-12 July 1991 P491-500. Publ Rotterdam: A A Balkema, 1991
A magnitude 3 seismic event occurred in the G Block crown pillar during a small open stope extension firing. It was associated with widespread displacement (up to 20mm) on the thin, rough Beta Fault. The nearby, parallel thick fault zone, the
An extensive microseismic monitoring system has been installed by the USBM in the Galena silver-copper mine in northern Idaho. Data from 2 stopes where rockburst occurred are presented. The degree of clustering of the event location
© 1992 Pergamon Press Ltd. Reproduction not permitted
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parameters, and energy distribution are described. Comparisons between the monitoring methods for understanding and forecasting rockburst are attempted. 924506 Keynote lecture: rock stress, structure and mine design Brady, B H G Pro¢ 2nd International Symposium on Rockbursts and Seismicity in Mines, Minneapolis, 8-10 June 1988 P311-321. Pubi Rotterdam: A A Balkema, 1990 The mechanics of rock mass deformation leading to transient instability are considered briefly, and techniques for numerical simulation and analysis of various modes of instability are discussed. Three computational schemes are considered: boundary elements, large-strain finite difference methods for elasto-plastic analysis, and distinct elements for analysis of true discontinuum behaviour. Some applications of these methods in mine excavation design are described, in identifying burst-prone conditions in a rockmass and in developing excavation layouts and sequences to alleviate the hazard of rockbursts. Finally, an analysis is presented which suggests hydraulic injection of slip-prone features may be applicable in mine stress control and rockburst hazard mitigation. 924509 Case studies on large rockbursts in South African gold mines Brummer, R K; Rorke, A J Proc 2nd International Symposium on Roekbursts and Seismicity in Mines, Minneapolis, 8-10 June 1988 P323-329. Publ Rotterdam: A A Balkema, 1990 Rockburst in South African gold mines can be classified into three categories on the basis of underlying mechanism: crush type, pillar foundation failure, and shear slip. The last mechanism, which is responsible for most of the largest events, is examined in detail with several large rockbursts described. By analysing mining layout, outburst, and post failure phenomena it is hoped to develop guidelines to help predict the location and extent of rockburst. 924510 Excess shear stress (ESS) - a case study Holmes, R D; Reeson, J A Proc 2nd International Symposium on Rockbursts and Seismicity in Mines, Minneapolis, 8-10 June 1988 P331-336. Publ Rotterdam: A A Balkema, 1990
Flanagan Fault, sheared by only 1.2mm. Two dimensional boundary element (BITEMJ) and three dimensional coupled boundary element-finite element (BEFE) modelling was used to study the event. Stress and ground movement have been monitored during subsequent mining. Position and orientation of the Beta Fault with respect to stope geometry are critical to initiation of shearing. Shear displacement depends on external loading and fault strength. 924512 Peak particle velocity for rock bursts in some Ontario mines Hedley, D G F Proc 2nd International Symposium on Rockbursts and Seismlcity in Mines, Minneapolis, 8-10 June 1988 P345-348. Publ Rotterdam: A A Balkema, 1990 Peak particle velocities were recorded during 25 rockbursts at the Creighton Mine in Sudbury and the Quirke and Denison Mines at Elliot Lake. Relations between ppv, distance from source, and magnitude of rockburst are examined in terms of conventional seismological and blasting equation formats. Best fit is found with a version of the blasting equation. Measured velocities are significantly lower than those from South African mines under similar conditions, which can be accounted for by greater attenuation of the seismic signals in the more fractured rock masses of Ontario. 924513 Results of prediction of seismic events in the territory of the Bohemian massif Buben, J; Rudajev, V Rock Mechanics as a Multidisciplinary Science: Proc 32nd US Symposium, Norman, 10-12 July 1991 P451-460. Publ Rotterdam: A A Balkema, 1991 Rockburst is a hazard in underground mines of all types in Czechoslovakia's Bohemian massif. Prediction of daily cumulative seismic energy and number of microseisms on the basis of simply measured mine parameters is attempted. Wiener extrapolation, adaptive filtration, and Bayesian (autoregressive) statistical techniques all produce similar results. 924514 Examination of energy calculations applied to coal bump prediction Heasley, K A Rock Mechanics as a Multidisciplinary Science: Proc 32nd US Symposium, Norman, 10-12 July 1991 P481-490. Publ Rotterdam: A A Balkema, 1991
Three of the four shafts of the Buffelsfontein Mine in Western Transvaal experience relatively high levels of seismicity. Following a magnitude 4.3 event in 1987 on Orangia Shaft, an investigation into the state of ESS on major strike oriented faults in the area was undertaken. The mining sequence from 1977-1987 was modelled using the computer program MINSIM D phase 3. 34 events of magnitude greater than 3 which occurred in the area of study in this period were examined to establish relations between physical parameters and ESS. Definite correlations are seen between length of fault exposed by mining, area mined, and seismic moment.
Pillar recovery in deep coal mines with competent roof and floor rock can lead to development of stress concentration and strain energy buildup, culminating in coal bumps. Although energy release rate methods have been used to indicate burst potential in hard rock mines, they have rarely been applied to coal mines. They are used with the displacement discontinuity code MULSIM/NL and field data in numerical simulation of underground coal mine behaviour. Suitability of different values of energy release for predicting coal bumps is examined.
924511 Interaction of slopes, stresses and geologic structure at Mount Charlotte Mine, Western Australia Lee, M F; Beer, G; Windsor, C R Proc 2nd International Symposium on Rockbursts and Sei;micity in Mines, Minneapolis, 8-10 June 1988 P337-343. Publ Rotterdam: A A Balkema, 1990
924515 New approaches to studying rock burst-associated seismicity in mines Coughlin, J; Kranz, R Rock Mechanics as a Multidisciplinary Science: Proc 32nd US Symposium, Norman, 10-12 July 1991 P491-500. Publ Rotterdam: A A Balkema, 1991
A magnitude 3 seismic event occurred in the G Block crown pillar during a small open stope extension firing. It was associated with widespread displacement (up to 20mm) on the thin, rough Beta Fault. The nearby, parallel thick fault zone, the
An extensive microseismic monitoring system has been installed by the USBM in the Galena silver-copper mine in northern Idaho. Data from 2 stopes where rockburst occurred are presented. The degree of clustering of the event location
© 1992 Pergamon Press Ltd. Reproduction not permitted