Experimental Nonlinear Dynamics and Chaos of Post-buckled Plates

Abstract

Panels and plates are an important structural element in many engineering applications, such as aircraft skin panels, ship hulls, and civil shell structures. These structures, particularly when their boundaries are in some way constrained, exhibit highly nonlinear behavior (e.g. spring hardening) even for relatively small deformations due to induced axial loading. An extreme, but highly important, example is dynamic snap-through buckling of curved or post-buckled thin panels. This phenomena is well represented in the literature, both for plates and for the simplified case of curved beams. The majority of the experimental studies, especially for panels, have been carried out using either wind tunnels or acoustic drivers to generate transverse loading. While this is directly applicable to real-world scenarios, say aircraft panel loading, it does not permit direct control of the loads that are applied. In this work, we instead apply loads to a thermally buckled panel using an electrodynamic shaker. This, along with the use of digital image correlation to capture the full field dynamic response allows for a complete picture of the complex characteristics of dynamic snap-through.