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Integral equation methods in fracture mechanics
211A 865321 Technical note - a theoretical model for outbursting in coal mines Paterson, L; Schlanger, H P
Bull Proc Austral lnst Min Metal ~90, NT, Not" 1985. P6769 A brief account of a theoretical model developed with the objective of helping in the prediction and prevention of outbursts in underground coal mines is presented. The basis of the outburst theory is that the outburst is the structural failure of coal due to excess stress resulting from body forces. Hence the proportional contributions of the role of gas and the role of stress in outburst can be calculated. The theory explains quantitatively why high rates of advance, coal of low permeability, coal with low strength or joints of low strength, mining at greater depth and mining with large pre-existing stresses tend to increase the occurrence of outbursts. 865322 Premature identification of gas-coal-outbursts by means of monitoring the gas contents (In German) Eicker, H; Kartenburg, H J
Gluckauf-forschungsh 1/47, N2, April 1986, P77-82 The methane content of a coal mine atmosphere was monitored over a period of four months, and statistical analysis was used to correlate mine atmosphere analysis with the rock and gas bursts occurring during this time, in an attempt to develop a method of predicting outburst. 865323 Analysis of a point sink embedded in a porous elastic half space Booker, J R; Carter, J P
lnt J Num Anal Meth Geomech VIO, N2. March-April 1986, P137-150 Closed-form solutions are presented for the steady-state distribution of displacements, pore pressure and stress around a point sink embedded in a homogeneous, isotropic elastic half space. These solutions have been evaluated for a typical case of a sink (pump) buried in sand and the magnitude of the settlement of the ground surface has been estimated. Auth. 865324 Effects of moisture variations and overburden on subsidence Elifrits, C D; Aughenbaugh, N B
Influence of dynamic loads 865326 Effects of seismic movement on underground space, with special reference to Kansas City, Missouri Loofbourow. R L
Underground Space V9, N4, 1985, P225-229 The history of tunnels, underground power houses, mine workings and oil wells in a number of seismically active zones, California, Chile, Japan, the Alps, is reviewed and used as a basis to evaluate the security from seismic damage of present and future underground developments in Kansas City, Missouri, USA. Many of the underground structures described have stood for centuries. It is concluded that, provided it is properly located, designed and constructed, underground space is remarkably resistant to seismic damage.
Subjects Peripheral to Geomechanics Fracture mechanics 865327 Integral equation methods in fracture mechanics Altiero, N J
Proc 5th Engineering Alechanics Division Speciality Conference, Wyoming, 1-3 Aug 1984 VI, P132-135. Publ New York: ASCE, 1984 Integral equation techniques are an attractive alternative to finite element methods in fracture mechanics, as difficulties associated with domain discretisation around the crack tip may be avoided. The crack surface can be described by dislocation density, displacement discontinuity and body force models, and it is shown that the various crack models derive from a single unified formulation, although their computational behaviour is quite different. The computation treatment of these equations is described and numerical results obtained using the various models are compared.
Min Engng 1/38, N2, Feb 1986, P115-119 Laboratory tests of samples of fine grained argillaceous rocks, commonly referred to as shales, have shown that various changes in their moisture content can be correlated with loss of strength. This reaction to a change of in situ conditions of abandoned mine sites, when combined with the field relationships at locations where the predominant overburden material is fine grained, argillaceous and fractured, provides a predictive tool for engineers dealing with subsidence problems. Such a tool should enable engineers to recognise areas prone to be affected by surface disturbing subsidence features. 865325 Time process of overburden movement (In Chinese) Li Bing
Q Changsha inst Min Res I/6, NI, March 1986, P54-60 A mathematical analysis is made of the surface movement of moderately competent overburden above a horizontal ore body extracted by longwall mining. New equations are proposed for surface movement and subsidence.
865328 Modelling the hydrofracture process as a coupled double free boundary problem Stout, g B
Proc 5th Engineering Atechanics Division Speciality Conference, Wyoming, 1-3 Aug 1984 VI, P559-562. Publ New York: ASCE, 1984 A three dimensional model of hydrofracture is presented, which treats the length and height of the crack without restraints. The crack geometry is an elliptical crack interior to a large volume. The analysis of the propagating hydrofracture involves determining the position-time history of two free boundaries, the crack tip position and the fluid front position for the fluid flowing in the fracture. A formulation of this double free boundary problem is described in terms of a rate variational principle.
© 1986 Pergamon Journals Ltd. Reproduction not permitted
Bull Proc Austral lnst Min Metal ~90, NT, Not" 1985. P6769 A brief account of a theoretical model developed with the objective of helping in the prediction and prevention of outbursts in underground coal mines is presented. The basis of the outburst theory is that the outburst is the structural failure of coal due to excess stress resulting from body forces. Hence the proportional contributions of the role of gas and the role of stress in outburst can be calculated. The theory explains quantitatively why high rates of advance, coal of low permeability, coal with low strength or joints of low strength, mining at greater depth and mining with large pre-existing stresses tend to increase the occurrence of outbursts. 865322 Premature identification of gas-coal-outbursts by means of monitoring the gas contents (In German) Eicker, H; Kartenburg, H J
Gluckauf-forschungsh 1/47, N2, April 1986, P77-82 The methane content of a coal mine atmosphere was monitored over a period of four months, and statistical analysis was used to correlate mine atmosphere analysis with the rock and gas bursts occurring during this time, in an attempt to develop a method of predicting outburst. 865323 Analysis of a point sink embedded in a porous elastic half space Booker, J R; Carter, J P
lnt J Num Anal Meth Geomech VIO, N2. March-April 1986, P137-150 Closed-form solutions are presented for the steady-state distribution of displacements, pore pressure and stress around a point sink embedded in a homogeneous, isotropic elastic half space. These solutions have been evaluated for a typical case of a sink (pump) buried in sand and the magnitude of the settlement of the ground surface has been estimated. Auth. 865324 Effects of moisture variations and overburden on subsidence Elifrits, C D; Aughenbaugh, N B
Influence of dynamic loads 865326 Effects of seismic movement on underground space, with special reference to Kansas City, Missouri Loofbourow. R L
Underground Space V9, N4, 1985, P225-229 The history of tunnels, underground power houses, mine workings and oil wells in a number of seismically active zones, California, Chile, Japan, the Alps, is reviewed and used as a basis to evaluate the security from seismic damage of present and future underground developments in Kansas City, Missouri, USA. Many of the underground structures described have stood for centuries. It is concluded that, provided it is properly located, designed and constructed, underground space is remarkably resistant to seismic damage.
Subjects Peripheral to Geomechanics Fracture mechanics 865327 Integral equation methods in fracture mechanics Altiero, N J
Proc 5th Engineering Alechanics Division Speciality Conference, Wyoming, 1-3 Aug 1984 VI, P132-135. Publ New York: ASCE, 1984 Integral equation techniques are an attractive alternative to finite element methods in fracture mechanics, as difficulties associated with domain discretisation around the crack tip may be avoided. The crack surface can be described by dislocation density, displacement discontinuity and body force models, and it is shown that the various crack models derive from a single unified formulation, although their computational behaviour is quite different. The computation treatment of these equations is described and numerical results obtained using the various models are compared.
Min Engng 1/38, N2, Feb 1986, P115-119 Laboratory tests of samples of fine grained argillaceous rocks, commonly referred to as shales, have shown that various changes in their moisture content can be correlated with loss of strength. This reaction to a change of in situ conditions of abandoned mine sites, when combined with the field relationships at locations where the predominant overburden material is fine grained, argillaceous and fractured, provides a predictive tool for engineers dealing with subsidence problems. Such a tool should enable engineers to recognise areas prone to be affected by surface disturbing subsidence features. 865325 Time process of overburden movement (In Chinese) Li Bing
Q Changsha inst Min Res I/6, NI, March 1986, P54-60 A mathematical analysis is made of the surface movement of moderately competent overburden above a horizontal ore body extracted by longwall mining. New equations are proposed for surface movement and subsidence.
865328 Modelling the hydrofracture process as a coupled double free boundary problem Stout, g B
Proc 5th Engineering Atechanics Division Speciality Conference, Wyoming, 1-3 Aug 1984 VI, P559-562. Publ New York: ASCE, 1984 A three dimensional model of hydrofracture is presented, which treats the length and height of the crack without restraints. The crack geometry is an elliptical crack interior to a large volume. The analysis of the propagating hydrofracture involves determining the position-time history of two free boundaries, the crack tip position and the fluid front position for the fluid flowing in the fracture. A formulation of this double free boundary problem is described in terms of a rate variational principle.
© 1986 Pergamon Journals Ltd. Reproduction not permitted