Experimental Nonlinear Dynamics and Snap-Through of Post-Buckled Composite Plates

Modern aerospace systems are beginning to see the use of composite panels and plates to achieve light weight and specific strength and stiffness. For constrained panels, thermally-induced axial loading may cause buckling of the structure, which can lead to nonlinear and potentially chaotic behavior. When post-buckled composite plates experience snap-through, they are subjected to large-amplitude deformations and in-plane compressive loading. These phenomena pose a potential threat to the structural integrity of composite structures. In this work, the nonlinear dynamics of post-buckled composite plates are investigated. In the experiment, an electrodynamic shaker is used to directly control the harmonic loads and the digital image correlation (DIC) technique is used to capture the dynamic response. Both chaotic (intermittent) and periodic (persistent) steady-state snap-through behaviors are investigated. The experimental results are compared to numerical analysis from a theoretical model based on the classical laminated plate theory (CLPT) using the von Karman strain-displacement relations.