An assumed strain method for the dispersive globallocal modeling of periodic structures
A computational method to ascertain the dispersive elastodynamic behavior of periodic materials is presented. The method is based on a two-field HuWashitzu variational formulation in which independent displacement and strain fields are employed. The method of multiple scales is used to recover a globallocal methodology, and an asymptotic analysis provides the characterization of the microstructure. The effectiveness of the methodology is assessed by computing the phase and group velocity spectra for time harmonic plane waves propagating in a laminated medium and a fiber-reinforced composite. Predicted results are compared with exact elasticity results, available experimental data, and other available predictions.
periodic structures elastodynamics wave propagation composite materials