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Showing 1 to 11 of 11 for “"Displacement Discontinuity"”.
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Solving three-dimensional problems in natural and hydraulic fracture development : insight from displacement discontinuity modeling
… of fractures. In this study, we implemented 3-D displacement discontinuity (DD) boundary element modeling to investigate the following intrinsically 3-D natural or hydraulic fracture propagation problems: the effect of fracture height on lateral propagation of vertical natural fractures, joint …
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Discontinuous modelling of strain localisation and failure
… when simulating failure in solids is to allow displacement discontinuities in the solution. In this work, different techniques, of varying complexity, are developed to simulate displacement discontinuities which are independent of the spatial discretisation using finite elements. The different …
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Estudo comparativo de formulações alternativas do método dos elementos de contorno para elasticidade bidimensional
… Element Method, Superposition Method and the Displacement Discontinuity Method were compared through computacional tests applied at internal and boundary points.
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A sharp interface isogeometric strategy for moving boundary problems
… with the Heaviside function which captures the displacement discontinuity. Meanwhile, the crack tips are enriched with asymptotic displacement functions to reproduce the tip singularity. The enriching degrees of freedom associated with the crack tips are chosen as stress intensity factors (SIFs) …
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An experimental and numerical study on the fracturing processes in Opalinus shale
… the bedding planes. FROCK, a model based on the Displacement Discontinuity Method (a type of Boundary Element Model) developed at MIT, was modified to incorporate the effect of bedding planes on the crack propagation patterns. A discontinuous critical strain criterion was implemented into the …
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Numerical modeling of mixed mode multiple crack propagation and its application to the simulation of nonlinear rock deformation and borehole breakout
… by making a series of modifications to the displacement discontinuity code of Crouch and Starfield (Crouch & Starfield, 1983). The most important modifications include modifying the boundary element for the calculation of stress intensity factors, adding Coulomb friction for closed portions …
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Modeling of crack initiation, propagation and coalescence in rocks
… can be incorporated in Finite Element (FE) and Displacement Discontinuity (DD) codes. Corresponding research has been going on at MIT and has led to the development of a DDM code - FROCK - which currently uses a stress-based criterion proposed by Bobet (1997) to model crack initiation and …
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Numerical Modelling of Seismic Activity at Tabular Orebody Mines in South Africa using the Boundary Element Method
… to possible seismic sources are represented by displacement discontinuity elements, and the corresponding failure thresholds are evaluated using the Limit Equilibrium Method and Coulomb-friction, Hoek-Brown and Mohr-Coulomb strength criteria. Unlike other methodologies that only accommodate …
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A Boundary Element Method for Thermo-poroelasticity with Applications in Rock Mechanics
… BEM has two sub-formulations, namely, the displacement discontinuity (DD) method and the fictitious stress (FS) method. The DD method has shown to be particularly suitable for crack-shaped problems (Crouch and Starfield, 1983). A combine FS-DD model is developed to take advantage of the …
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THREE-DIMENSIONAL MODELING OF HYDRAULIC AND NATURAL FRACTURE INTERACTIONS AND ITS APPLICATIONS IN RESERVOIR STIMULATION
… are modeled using two- and three-dimensional displacement discontinuity (DD) method. Contact elements are used to represent the closed natural fractures along with the Mohr-Coulomb criterion to determine the contact status of the fractures. Fracture propagation is modeled using a mixed-mode …
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Characterization of Fractures Subjected to Normal and Shear Stress
… specific stiffnesses were calculated using the displacement discontinuity theory. For non-mated fractures, the stiffness ratio was not sensitive to the application of shear stress and, as normal stress increased, approached a theoretical ratio which was determined assuming that the transmission …