Symmetric boundary element method versus finite element method

The paper examines the effectiveness of the symmetric boundary element formulation when the continuum body is subdivided into large elements called macro-elements. The approach proposed combines a strong reduction of variables with an elastic solution close to the real response. Indeed, if the displacement method is used, this approach permits one to determine for every macro-element a relationship connecting the weighted traction vector defined on the sides of the interface boundary with the node displacement vector of the same boundary and with the external action vector. Such a strategy is very similar to that followed through the finite element method, but with the advantages of having the punctual satisfaction of the equilibrium and compatibility by using the fundamental solution, and of employing large elements whose discretization is performed on the boundary only. Some examples are shown using a general computing programme developed by the present authors.