Novel PU/NF damper featuring compression-shear and flexural-shear synergistic energy dissipation and temperature insensitivity

The thermal sensitivity of viscoelastic materials has long constrained the performance of structural dampers. This study resolves this critical issue by developing a novel polyurethane/nickel foam (PU/NF) composite with exceptional thermal stability. By embedding open-cell NF, a material with intrinsically temperature independent energy dissipation, into a PU matrix, we effectively neutralized the polymer’s performance fluctuations. Based on this material, we designed and tested a novel shear-flexural damper that leverages a synergistic mechanism of compression-shear and flexural-shear actions to maximize energy dissipation. Dynamic tests confirmed that the PU/NF composite and the resulting damper maintain stable performance across a wide temperature range. Furthermore, a thermodynamic theoretical model accurately predicts the experimental hysteresis curves, validating our understanding of the synergistic dissipation mechanism. This work presents a robust PU/NF damper that delivers reliable and superior energy dissipation under large displacements and variable thermal conditions, advancing the seismic protection of structures in demanding environments.