Nonlinear oscillations of a harmonically excited composite structure

Abstract An experimental study was conducted of the nonlinear forced response of an internally-resonant composite structure to primary resonant excitations. Coupling between the directly excited and indirectly excited modes of vibration of the structure leads to nonlinear periodic, periodically modulated, and chaotically modulated responses. Some of the observed nonlinear responses are nonplanar due to interaction between flexural and torsional modes of vibration. Experimental results are presented and compared with those obtained in earlier studies of a metallic structure having a similar form.