Large deformation of square plates under pulse loading by combined saturation analysis and membrane factor methods

Thin plates will experience large deformation under intense pulse loading, which may result in serious consequences. Numerous research work has been conducted since 1950s and some theoretical methods have been developed to predict the large deformation of plates based on Rigid-Plastic Idealization of material behavior. However, even with this idealization, it is often difficult to obtain complete solutions. Membrane Factor Method (MFM) has proved a powerful method to solve this problem, resulting in solutions taking into account of the effects of the transient phase and the interaction between membrane force and bending moment through a relatively simple procedure. On the other hand, Saturation Analysis (SA) based on the saturation phenomenon is more rational and accurate than the traditional analyses using total impulse of pulse loading. This paper combines these two approaches to study the dynamic plastic response of square plates under rectangular pressure pulse and linear decay pressure pulse loading, and then the results are compared with modal solutions and FE simulations. Meanwhile, the solutions of this combined method, which merely considers the modal phase are also provided to identify the effect of the transient phase. Finally, two sets of simple calculation formulae are proposed for the permanent deformation of plates so as to facilitate engineering applications.