BOUNDARY ELEMENT SOLUTIONS FOR FREQUENCY DOMAIN PROBLEMS IN MINDLIN's STRAIN GRADIENT THEORY OF ELASTICITY

An advanced Boundary Element Method (BEM) for solving two-dimensional (2D), frequency domain, elastodynamic problems in materials with microstructural effects is presented. The analysis is performed in the context of Mindlin's Form II gradient elastic theory. The frequency domain Form II gradient elastodynamic fundamental solution of the equation of motion is employed, while the integral representation of the problem, consisting of two boundary integral equations, one for displacements and the other for its normal derivative is utilized. The global boundary of the analyzed domain is considered smooth without corners, discetized into quadratic line elements. A representative 2D numerical example is provided to illustrate the method, demonstrate its accuracy and assess the gradient effect on the response.