Background <p>The first vertical bending frequency of a railway carbody typically lies within the range of human sensitivity to vertical vibrations. At higher operating speeds, excitation frequencies increase and may approach this bending frequency, leading to resonance and reduced ride comfort.</p> Purpose <p>This study investigates methods to mitigate vertical vibrations associated with the first carbody bending mode by examining the effects of secondary suspension stiffness, carbody bending stiffness, and elastically suspended under-chassis equipment (UCE).</p> Methods <p>The influence of these parameters on carbody vibration characteristics was evaluated through numerical simulations. The numerical model was validated by comparing simulated and experimental natural frequencies and mode shapes.</p> Results <p>Increasing bogie secondary suspension stiffness raises the first bending frequency of the carbody system but simultaneously amplifies the vibration magnitude. Incorporating a properly designed anti-bending bar effectively increases carbody bending stiffness and shifts the first bending frequency upward without significantly adding mass. In addition, elastically suspended UCE can reduce first-bending-mode vibrations when supported with appropriate stiffness and positioned optimally.</p> Conclusions <p>The study demonstrates that increasing carbody bending stiffness using an anti-bending bar is the most effective approach for mitigating vertical vibrations induced by the first bending mode. Nevertheless, optimising bogie suspension parameters, UCE support stiffness, and UCE layout also play a crucial role in improving overall ride comfort.</p>