Dynamic analysis of non-uniform motion of Mindlin plate subjected to a moving mass-spring-damper system using the Moving Element Method

This study examines the dynamic response of a Mindlin plate on a Pasternak foundation under a moving mass-spring-damper system with variable velocity, employing the Moving Element Method (MEM). The model incorporates bending and shear deformations, discretized via high-order quadrilateral elements, and accounts for foundation stiffness and surface roughness as dynamic excitation sources. Governing equations are derived using the virtual work principle in a moving coordinate system. Validated against benchmark solutions, the analysis reveals that surface roughness significantly amplifies displacement and stress responses, with specific load velocity-wavelength combinations inducing resonance. Parametric studies highlight the influence of load velocity, spring stiffness, damping, and plate thickness on structural behavior, underscoring the critical role of surface quality in ensuring dynamic stability and load-carrying capacity. Unlike previous works assuming constant-velocity loading, this study incorporates non-uniform motion profiles, thereby providing a more realistic framework for moving load problems. The results not only advance theoretical understanding but also offer practical guidance for the design of resilient pavements and bridge decks under dynamic excitations.