Dynamic collapse characteristics of rectangular plate under periodic load and slamming load

• Dynamic stability of the rectangular plate is investigated, and plastic accumulation after instability is analyzed using the NFEM. • Elastoplastic dynamic response under slamming loads is simulated, with structural failure modes captured through numerical simulations. • Dynamic collapse under periodic and slamming loads is assessed, incorporating structural failure analysis to preliminarily explore the coupled load effects. Ships experience time-varying dynamic loads during navigation, including periodic wave load and slamming load. This study investigates the dynamic collapse behavior of a typical ship plate through theoretical and numerical analyses. Dynamic instability loads of the rectangular plate are calculated based on dynamic stability theory, while the slamming response is analyzed using elastic plate dynamic equations, focusing on damping and static load effects. Additionally, the structural elastoplastic dynamic response is simulated using nonlinear finite element method, identifying structural collapse modes under critical slamming load and exploring the influences of slamming duration and periodic loading. Results indicate that periodic loading significantly reduces the critical slamming load, where dynamic instability induces plastic accumulation in the structure, leading to a rapid reduction in its slamming load-bearing capacity. This study provides guidance for analyzing the dynamic response and ultimate strength of hull structures under dynamic wave conditions.