Y-Geo: New Combined Finite-Discrete Element Numerical Code for Geomechanical Applications
Publication: International Journal of Geomechanics
Volume 12, Issue 6
Abstract
The purpose of this paper is to present Y-Geo, a new numerical code for geomechanical applications based on the combined finite-discrete element method (FDEM). FDEM is an innovative numerical technique that combines the advantages of continuum-based modeling approaches and discrete element methods to overcome the inability of these methods to capture progressive damage and failure processes in rock. In particular, FDEM offers the ability to explicitly model the transition from continuum to discontinuous behavior by fracture and fragmentation processes. Several algorithmic developments have been implemented in Y-Geo to specifically address a broad range of rock mechanics problems. These features include (1) a quasi-static friction law, (2) the Mohr-Coulomb failure criterion, (3) a rock joint shear strength criterion, (4) a dissipative impact model, (5) an in situ stress initialization routine, (6) a material mapping function (for an exact representation of heterogeneous models), and (7) a tool to incorporate material heterogeneity and transverse isotropy. Application of Y-Geo is illustrated with two case studies that span the capabilities of the code, ranging from laboratory tests to complex engineering-scale problems.
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Acknowledgments
This work was supported by NSERC/Discovery Grant No. 341275 and NSERC/RTI Grant No. 345516, an Ontario Graduate Scholarship in Science and Technology held by O. K. Mahabadi, and an Ontario Graduate Scholarship held by A. Lisjak. The writers wish to thank Tomas Lukas for his help during the code developments and Dr. Fereidoun Rezanezhad for assistance with image processing. The writers are also grateful to Bryan Tatone for reviewing, discussion, and constructive comments on this paper.
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Published In
International Journal of Geomechanics
Volume 12 • Issue 6 • December 2012
Pages: 676 - 688
Copyright
© 2012 American Society of Civil Engineers.
History
Received: Apr 26, 2011
Accepted: Mar 7, 2012
Published online: Mar 12, 2012
Published in print: Dec 1, 2012
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