The last three decades have been marked by the evolution of electronic computers and an enormous and wide-spread availability of computational power.
This has boosted the development of computational methods and their application in engineering and in the analysis and design of structures, which extend from bridges to aircrafts and from machine elements to tunnels and the human body.
New scientific subfields were generated in all engineering disciplines being described as "Computational", e.g. Computational Mechanics, Computational Fluid Mechanics, Computational Structural Analysis, Computational Structural Dynamics etc.
The Finite Element Method (FEM) and the Boundary Element Method (BEM) are the most popular of the computational methods.
While the FEM has been long established and is most well known in the engineering community, the BEM appeared later offering new computational capabilities with its effectiveness, accuracy and low computational cost.
Although the BEM is taught as a regular course at an ever increasing number of universities, there is a noticeable lack of a textbook which could help students as well as professional engineers to understand the method, the underlying theory and its application to engineering problems.
An essential reason is that BEM courses are taught mainly as advanced graduate courses, and therefore much of the underlying fundamental knowledge of mathematics and mechanics is not covered in the respective undergraduate courses.
Thus, the existing books on BEM are addressed rather to academia and researchers who, somehow, have already been exposed to the BEM than to students following a BEM course for the first time and engineers who are using boundary element software in industry.
This observation stimulated the author to write the book at hand. His research in the development of BEM during the last 25 years as well as the experience he acquired by teaching for many years the course of Boundary Elements at the Civil Engineering Department of the National Technical University of Athens, Greece, justify this endeavor.
The author's ambition was to make BEM accessible to the student as well to the professional engineer. For this reason, his main task was to organize and present the material in such a way so that the book becomes "userfriendly" and easy to comprehend, taking into account only the mathematics and mechanics to which students have been exposed during their undergraduate studies.
This effort led to an innovative, in many aspects, way of presenting BEM, including the derivation of fundamental solutions, the integral representation of the solutions and the boundary integral equations for various governing differential equations in a simple way minimizing a recourse to mathematics with which the student is not familiar.
The indicial and tensorial notations, though they facilitate the authors' work and allow to borrow ready to use expressions from the literature, have been avoided in the present book. Nevertheless, all the necessary preliminary mathematical concepts have been included in order to make the book complete and self-sufficient.
In closing, the author would like to express his sincere thanks to his former student and Visiting Assistant Professor at Texas A&M University Dr. Filis Kokkinos for his carefully reading the manuscript and his suggestions for constructive changes.
His critic and comments are greatly appreciated. Thanks also belong to my doctoral student Mr. G.C. Tsiatas, M.Sc., for checking the numerical results and the derivation of several expressions.