抄録
Experimental result are presented on nonlinear vibrations of a bi-stable CFRP laminated curved plate. The CFRP plate is fixed at center with bolts. The CFRP plate has two equilibrium configurations which is an upward convex and a downward convex. The characteristics of restoring force are measured in which asymmetric configurations appears in the transition between two stable equilibrium position.The natural frequencies are measured by impulse force. Moreover, natural modes of vibration are measured applying infinitesimal acoustic pressure. Next, the CFRP plate is exited with periodic acceleration by the electromagnetic shaker. Sweeping the excitation frequency, responses of the plate are measured by laser displacement sensors. Under uniform lateral periodic excitation, principal resonance with higher harmonics components is observed in large amplitude showing the characteristics of softening spring. Furthermore, sub-harmonic resonance of 1/2 order is generated when a concentrated mass is attached at a corner of the plate in downward convex which induces an asymmetric deformation.
