Experimental and mechanical performance analysis of novel sparrow brace type viscoelastic dampers
The article proposes a novel sparrow brace type viscoelastic damper.In order to study the rationality and feasibility of its structural form,cyclic loading tests were conducted on five of these new sparrow brace type viscoelastic dampers,examining deformation correlation,frequency correlation,and fatigue performance.The analysis included the evaluation of several performance parameters of the new sparrow brace type viscoelastic dampers,such as energy dissipation coefficients,equivalent viscous damping ratios,and skeleton curves.Research results show that the hysteresis loops of the five new sparrow brace type viscoelastic dampers are full,indicating excellent hysteresis performance and strong energy dissipation capability.For specimens with a rubber hardness of 65°,the cumulative energy dissipation is 2.343 kN·m.The influence of deformation amplitude on the damper is evident.As the deformation increases,the maximum damping force and cyclic energy dissipation of damper gradually increase,while the energy dissipation coefficient and equivalent stiffness gradually decrease.The hysteresis loops,equivalent viscous damping ratios,and skeleton curve shapes of specimens with different rubber materials for the new sparrow brace type viscoelastic dampers are basically consistent.Under different loading frequencies,the energy dissipation coefficients range from 0.03962 to 0.04016,and the equivalent viscous damping ratios range from 0.1260 to 0.1320.Both performance indicators exhibit relatively minor changes,suggesting a weak correlation with frequency.After fatigue loading,the energy dissipation coefficient of the new viscoelastic damper decreases by 24.8%,and the equivalent viscous damping ratio decreases by 25.4%,demonstrating excellent fatigue performance without a significant reduction in hysteresis loop area or the occurrence of low-cycle fatigue phenomena.
timber structure reinforcementnovel sparrow brace type viscoelastic damperdeformation correlationfrequency correlationfatigue performancehysteretic energy