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  • 1
    Electronic Resource
    Electronic Resource
    Scaling Laws for the Design of Rock Support (1997)
    Springer
    Pure and applied geophysics 150 (1997), S. 415-434 
    Details
    ISSN: 1420-9136
    Keywords: Key words: Scaling laws, rockburst, induced seismicity, ground motion, peak particle velocity.
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    Notes: Abstract. —The dynamic loads imposed by rockbursts initiated by remote seismic events are directly related to the resultant ground motions. Consequently, the first step in the design of systems for the support of openings subject to such loading is to assess the ground motion characteristics; i.e., to evaluate the peak particle velocity ppv in the design region. Design scaling laws, relating seismic source intensity (event magnitude, radiated energy or a combination of seismic moment and stress drop at the source) to the peak ground motion characteristics at a target (e.g., a development drift or a stope) some distance from the source, are developed, based upon theoretical considerations and supported by a world-wide database. These scaling laws reflect the most relevant, critical conditions for engineering design.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s000240050085
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  • 2
    Electronic Resource
    Electronic Resource
    A Tensile Model for the Interpretation of Microseismic Events near Underground Openings (1998)
    Springer
    Pure and applied geophysics 153 (1998), S. 67-92 
    Details
    ISSN: 1420-9136
    Keywords: Key words: Microseismic event, seismic energy, source size, stress-induced fracturing, tensile fracturing.
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    Notes: Abstract —For small-scale microseismic events, the source sizes provided by shear models are unrealistically large when compared to visual observations of rock fractures near underground openings. A detailed analysis of the energy components in data from a mine-by experiment and from some mines showed that there is a depletion of S-wave energy for events close to the excavations, indicating that tensile cracking is the dominant mechanism in these microseismic events.¶In the present study, a method is proposed to estimate the fracture size from microseismic measurements. The method assumes tensile cracking as the dominant fracture mechanism for brittle rocks under compressive loads and relates the fracture size to the measured microseismic energy. With the proposed method, more meaningful physical fracture sizes can be obtained and this is demonstrated by an example on data from an underground excavation with detailed, high-quality microseismic records.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s000240050185
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  • 3
    Electronic Resource
    Electronic Resource
    Use of Microseismic Source Parameters for Rockburst Hazard Assessment (1998)
    Springer
    Pure and applied geophysics 153 (1998), S. 41-65 
    Details
    ISSN: 1420-9136
    Keywords: Key words: Rockbursts, hazard assessment, microseismicity, source parameters.
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    Notes: Abstract —Since 1994 Noranda’s Brunswick #12 Mine has complemented their MP250/Queen’s Full Waveform seismic systems with an ISS (Integrated Seismic System). Time histories of ISS source parameter information form a component of the daily ground control decision-making. This paper discusses a methodology for microseismic hazard assessment, which filters ISS data using energy, apparent stress and seismic moment criteria to identify those events that are relevant for the assessment and decision-making process. Seismic events are classified into four groups (1) no or minor hazard; (2) seismically-triggered, gravity-driven hazards; (3) stress-adjustment-driven hazards resulting in bulking due to rock mass fracturing; and (4) deformation-driven hazards exploiting existing rock mass damage. Three case histories from 1994–1996, for the 1000 Level South and the 850 Level at Brunswick Mine, are analyzed using this technique to calibrate and verify the proposed methodology.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s000240050184
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  • 4
    Electronic Resource
    Electronic Resource
    Stress determination by back-analysis of excavation-induced stress changes — a case study (1990)
    Springer
    Rock mechanics and rock engineering 23 (1990), S. 185-200 
    Details
    ISSN: 1434-453X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Architecture, Civil Engineering, Surveying , Geosciences
    Notes: Summary An Underground Research Laboratory (URL) has been constructed by Atomic Energy of Canada Limited (AECL) to study various aspects of disposing of nuclear fuel waste in the Canadian Shield. In order to ensure good quality and long life of the construction, one important factor to be considered is the in situ stress field. As part of the research program, stress changes have been measured during the advance of a tunnel to monitor the stress response to excavation. It is desirable to estimate the state of in situ stress from these stress change measurements and to compare the results with overcoring data. This paper describes the application of a recently developed stress change fitting technique for stress determination. The basic principle and the fitting procedure are briefly summarized and the back-analysis process for the data collected at the URL is presented in detail. A boundary element model was used to predict the stress changes as required by the fitting approach. This new method of in situ stress determination was successfully applied in this case. The back-analyzed stresses agree very well with those determined from overcoring tests. The quality of individual measurements was assessed and the required minimum number of measurements for a conclusive data interpretation is evaluated.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01022953
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  • 5
    Electronic Resource
    Electronic Resource
    Determination of in situ stresses from excavation-induced stress changes (1990)
    Springer
    Rock mechanics and rock engineering 23 (1990), S. 167-184 
    Details
    ISSN: 1434-453X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Architecture, Civil Engineering, Surveying , Geosciences
    Notes: Summary The state of in situ stress described by the magnitudes and orientations of the principal stresses is an important design parameter for the construction of underground openings. Conventional methods of in situ stress determination, such as overcoring, only provide information for a small domain and are usually very costly. In this paper, a method for field stress determination in a volume of rock that is representative for an underground opening is presented. This method requires the measurement of stress changes induced by the excavation of an opening (tunnel). The best fit stress field is then determined by comparing measured and predicted stress changes. An error function is defined between the two sets of stress changes and the best-fit solution is obtained by error minimization. The methodology and its applicability are explained by an example of a circular opening for which closed form solutions are available. Application of this method to a case study has shown great potential. The back-analyzed stresses are extremely close to those determined by a large number of overcoring tests. Compared with conventional techniques of stress determination, this new method is superior in that: (1) the stress information can be updated during construction; (2) it gives the stress state in a relatively large volume of rock rather than at a point; and (3) most important, it is relatively inexpensive.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01022952
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  • 6
    Electronic Resource
    Electronic Resource
    Effects of rock mass anisotropy and non-linearity on the near face stresses in deep tunnels (1995)
    Springer
    Rock mechanics and rock engineering 28 (1995), S. 125-132 
    Details
    ISSN: 1434-453X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Architecture, Civil Engineering, Surveying , Geosciences
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01020065
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  • 7
    Electronic Resource
    Electronic Resource
    Practical application of an innovative microseismic source location procedure (1992)
    Springer
    Geotechnical and geological engineering 10 (1992), S. 163-184 
    Details
    ISSN: 1573-1529
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences
    Notes: Summary A detailed case study conducted at a Canadian gold mine is presented to demonstrate the practical usefulness of the source location data analysis theory developed by Ge and Kaiser (1990). The basic concept of the theory and the interpretation of the physical status of wave arrival picks is explained through a step-by-step analysis of several microseismic events. The effectiveness of the theory is illustrated by statistical data analysis. It is demonstrated that the theory enhances MP250 systems by providing an automatic microseismic source location technique.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00881170
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  • 8
    Electronic Resource
    Electronic Resource
    Analytical model for the design of grouted rock bolts (1990)
    New York, NY [u.a.] : Wiley-Blackwell
    International Journal for Numerical and Analytical Methods in Geomechanics 14 (1990), S. 227-251 
    Details
    ISSN: 0363-9061
    Keywords: Engineering ; Engineering General
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Architecture, Civil Engineering, Surveying , Geosciences
    Notes: An analytical model which represents the behaviour of a reinforced rock mass near a circular underground opening in a homogeneous, uniform stress field has been developed. The theory adopts the concepts of elastoplasticity and considers a proper interaction mechanism between the ground and the grouted (or friction) bolts. It highlights the influence of the bolt pattern on the extent of the yield zone and tunnel deformation. A dimensionless parameter is introduced as a design tool which relates the tunnel convergence to the bolt spacing for a given bolt length. This publication contains the derivation of the analytical model and an illustration of the effect of bolts on the stress and displacement field near an opening. Its application to tunnel design is discussed briefly. The verification of the theory by laboratory simulation and field measurements will be presented, in detail, in a future publication.
    Additional Material: 16 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/nag.1610140402
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  • 9
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    Influence of persistence on behaviour of fractured rock masses (2007)
    In:  Geological Society Special Publication 284: 161-173.
    Details
    Publication Date: 2007-12-12
    Description: Most of the models that simulate fractured rock masses assume fully persistent discontinuities, simplifying the fact that, in nature, fractured rock masses are made of non-continuous sets of joints. A rock bridge gives an effective cohesion to the fracture and a block of rock cannot fall or slide until all the rock bridges fail. This failure involves the failure of the intact rock, which can be orders of magnitude stronger than the shear strength of the rock joint. In this study we focus on how the distribution of rock bridges influences the overall rock mass behaviour, to contribute to the understanding of how the presence of rock bridges influences the scale' effect that is observed between strength values measured on intact rock in the laboratory and those observed at the rock mass scale. To estimate the influence of spatial fracture, parameters of the rock mass strength and deformation were determined, using the orthogonal arrays method, UDEC and variance analysis. The numerical model was first calibrated on shear tests of samples made of continuous joints, and then used to investigate the shear behaviour of a fractured rock mass with non-persistent joints. The 2D approach was successfully extended to 3D models using 3DEC with the aim of providing a better approach for simulating the stability of an underground cavern in a fractured rockmass.
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    PAPER
  • 10
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    Practical application of an innovative microseismic source location procedure (1992)
    Springer
    Details
    Publication Date: 1992-09-01
    Print ISSN: 0960-3182
    Electronic ISSN: 1573-1529
    Topics: Geosciences
    Published by Springer
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