Numerical techniques for solving many problems in continuum mechanics have experienced a tremendous growth in the last twenty years due to the development of large high speed computers. In particular, geomechanical stress analysis can now be modelled within a more realistic context. In spite of the fact that many applications in geomechanics are still being carried out applying linear theories, soil and rock materials have been demonstrated experimentally to be physically nonlinear. Soils do not recover their initial state after removal of temporary loads and rock does not deform in proportion to the loads applied. The search for a unified theory to model the real response of these materials is impossible due to the complexities involved in each case. Realistic solutions in geomechanical analysis must be provided by considering that material properties vary from point to point, in addition to other significant features such as non-homogeneous media, in situ stress condition, type of loading, time effects and discontinuities. A possible alternative to tackle such a problem is to inttoduce some simplified assumptions which at least can provide an approximate solution in each case. The validity or accuracy of the final solution obtained is always dependent upon the approach adopted. As a consequence, the choice of a reliable theory for each particular problem is another difficult decision which should be 2 taken by the analyst in geomechanical stress analysis.

Numerical techniques for solving many problems in continuum mechanics have experienced a tremendous growth in the last twenty years due to the development of large high speed computers. In particular, geomechanical stress analysis can now be modelled within a more realistic context. In spite of the fact that many applications in geomechanics are still being carried out applying linear theories, soil and rock materials have been demonstrated experimentally to be physically nonlinear. Soils do not recover their initial state after removal of temporary loads and rock does not deform in proportion to the loads applied. The search for a unified theory to model the real response of these materials is impossible due to the complexities involved in each case. Realistic solutions in geomechanical analysis must be provided by considering that material properties vary from point to point, in addition to other significant features such as non-homogeneous media, in situ stress condition, type of loading, time effects and discontinuities. A possible alternative to tackle such a problem is to inttoduce some simplified assumptions which at least can provide an approximate solution in each case. The validity or accuracy of the final solution obtained is always dependent upon the approach adopted. As a consequence, the choice of a reliable theory for each particular problem is another difficult decision which should be 2 taken by the analyst in geomechanical stress analysis.

2D/3D Boundary Element Programming in Petroleum Engineering and Geomechanics, Volume 72, is designed to make it easy for researchers, engineers and students to begin writing boundary element programs. This reference covers the fundamentals, theoretical developments, programming and applications. Both fluid flow through porous media and structural problems are used for coding exercises. Included computer programs may be used as starting codes; after modifications, they can be applied to real world problems. The book covers topics around mesh generation, 3D boundary element coding, and interface coding for controlling mesh generation, and plotting results. - Includes interactive 2D and 3D coding exercises that readers can modify based on need - Features research on the most recent developments in indirect and dual boundary element methods - Contains case studies showing examples and applications of the theories presented in the book

This book is an introduction to numerical analysis in geomechanics and is intended for advanced undergraduate and beginning graduate study of the mechanics of porous, jointed rocks and soils. Although familiarity with the concepts of stress, strain and so on is assumed, a review of the fundamentals of solid mechanics including concepts of physical laws, kinematics and material laws is presented in an appendix. Emphasis is on the popular finite element method but brief explanations of the boundary element method, the distinct element method (also known as the discrete element method) and discontinuous deformation analysis are included. Familiarity with a computer programming language such as Fortran, C++ or Python is not required, although programming excerpts in Fortran are presented at the end of some chapters. This work begins with an intuitive approach to interpolation over a triangular element and thus avoids making the simple complex by not doing energy minimization via a calculus of variations approach so often found in reference books on the finite element method. The presentation then proceeds to a principal of virtual work via the well-known divergence theorem to obtain element equilibrium and then global equilibrium, both expressed as stiffness equations relating force to displacement. Solution methods for the finite element approach including elimination and iteration methods are discussed. Hydro-mechanical coupling is described and extension of the finite element method to accommodate fluid flow in porous geological media is made. Example problems illustrate important concepts throughout the text. Additional problems for a 15-week course of study are presented in an appendix; solutions are given in another appendix.

The editors have published a select group of full length papers on boundary element analysis (BEA) photographed from camera ready manuscripts. The articles have been prepared by some of the most distinguished and prolific individuals in this field. More than half of these articles have been submitted by authors that participated in an International Forum on Boundary Element Methods, in Melbourne Australia, in the Summer of 1991. However, this volume is not a conference proceedings, as these authors have expanded their accounts to chapter length, and/or have tailored their expositions more toward the style employed in archival journal publications. The authors that did not participate in the International Forum have also adhered to the above mentioned philosophy. This work contains a definitive representation of the significant capabilities and applications currently available or under investigation that fall under the general category of advanced boundary element analysis. With treatments of mechanical, thermal, fluid, and electromagnetic phenomena, this book should thus be of value to graduate students, practitioners, and researchers in engineering, mathematics, and the physical sciences wishing to obtain a broader perspective or remain current in these important areas of computational simulation.

The IUTAM Symposium on Advanced Boundary Element Methods brought together both established and current researchers in the broad context of applications of BEM technology. The goal of the Symposium was to provide both a formal and an informal forum for the interchange of ideas and the stimulation of new research directions.