新型黏弹性阻尼器足尺性能试验研究

黏弹性阻尼器是一种典型的被动控制装置,它可以通过黏弹性材料的剪切滞回耗能起到提高结构阻尼和减小结构地震或风振响应的作用。自主研发了损失系数不小于0.5的黏弹性材料,并基于此材料研发了新型国产黏弹性阻尼器。通过对黏弹性阻尼器足尺试件进行不同应变幅值、加载频率工况下的基本力学性能试验、以及低周疲劳性能试验,研究了不同工况下新型黏弹性阻尼器力学参数及其变化规律。试验结果表明:新型黏弹性阻尼器的损失系数在多数工况下处于0.3~0.4之间;其基本力学性能与加载频率相关性较小,随着应变幅值的增加表现出一定程度的软化特征,但在各应变幅值下均具有稳定的耗能能力;新型黏弹性阻尼器有良好的变形能力,在150%的应变下能保持稳定的基本力学性能,应变350%时仍未破坏;新型黏弹性阻尼器的疲劳性能较好,经低周疲劳加载后各项基本力学指标变化率均不超过25%。

Full-scale Experimental Study on the Performance of a Novel Viscoelastic Damper

Viscoelastic dampers dissipate energy through the shear deformation of viscoelastic materials; thus, they can provide additional damping and reduce structural responses during earthquakes and winds. In this study, a viscoelastic material with loss coefficient of less than 0.5 was developed, and a novel domestic viscoelastic damper was obtained based on this material. An experimental study of the novel viscoelastic damper was conducted by using full-scale specimens. Strain amplitude and loading frequency were chosen as test parameters, and shear storage modulus, shear loss modulus, and loss factor of the damper under different loading schemes were investigated. Low-cycle fatigue tests were also conducted. The test results suggest that the loss coefficient of the damper is about 0.3-0.4 for most cases. The correlation between basic mechanical properties of the damper and loading frequency is small, and the energy dissipation capacity of the damper is stable under different loading amplitudes. The damper shows good deformability as it can maintain stable mechanical properties at a strain amplitude of 150% and is not damaged when the strain amplitude is 350%. The damper also exhibits satisfactory low-cycle fatigue behavior since its mechanical behavior does not change significantly after 30 cycles of loading.