Load-bearing and damping performance of composite steel pedestals with negative-Poisson’s-ratio honeycomb

To address fatigue failure, weld cracking and resonance in steel-frame pedestals caused by mechanical vibration, this study proposes a composite steel frame fabricated by integrating concave hexagonal negative-Poisson’s-ratio honeycomb structures with I-shaped steel, aiming to achieve the integrated structural function of load bearing and vibration damping. Bending and vibration tests are carried out on both conventional and composite steel frames to compare their static load-bearing characteristics and dynamic vibration-damping effects. Meanwhile, a finite-element model is established based on the Abaqus software platform to explore the regulation mechanism of honeycomb geometric parameters on the composite frame’s performance. Results show the composite frame realises ‘load-bearing–vibration-damping’ synergy, with yield strength basically consistent with conventional frames and excellent low-frequency vibration energy dissipation capacity. Honeycomb arrangement position and cell thickness mainly regulate load-bearing performance, while layer number and cell thickness have a significant impact on damping. After parameter optimisation, the maximum vibration level difference of the composite frame peaks at 62.81 dB, providing new design ideas and technical support for steel frame performance optimisation under low-frequency vibration environments.