SMA阻尼器偏心结构平-扭震动控制试验研究

为了验证提出的新型筒式自复位形状记忆合金阻尼器(telescopic recentering shape memory al-loy damper,TRSMAD)对结构平动-扭转耦联振动反应的抑制作用,进行了偏心结构消能减震体系的振动台试验。设计了一个1/4缩尺的三层两跨单向偏心的钢框架模型,将提出的新型SMA阻尼器安装在结构底层的一侧,通过振动台分别对无控条件下和装有阻尼器的有控条件下的结构反应进行了研究。试验结果表明:(1)在各地震波作用下,TRSMAD对结构的平动反应有很好控制效果,而对结构各层扭转角位移的控制效果稍低;(2)不同地震波下的控制效果有所不同:对结构的平动位移而言,天津波的减震率最高,El Centro波次之,最后为Taft波;对结构扭转角的控制,平均而言,除了天津波作用下第二层为特例外,对El Centro波的减震效果最好,其次为Taft波,最后为天津波;(3)同一地震波下,阻尼器对结构模型一层的位移控制效果较其他层为优。

Experimental study on horizotal-torsional coupled vibration control of eccentric structure with SMA damper

In order to verify the effectiveness of innovative telescopic recentering shape memory alloy damper(TRSMAD) in mitigating the translational-torsional coupled response of eccentric structures,shaking table tests on a reduced-scale eccentric steel frame model with and without TRSMAD-based energy dissipation system were performed.A 1/4-scale,3-story,2-span steel frame model of building with eccentricity was designed.One TRSMAD was eccentrically installed in the bottom story of the model.The building model with and without TRSMAD-based energy dissipation system were tested through shake table.The experimental results show that the TRSMAD can significantly reduce translational vibration and slightly mitigate the torsion response of buildings.However,the reduction ratio is different for different earthquake records.As for translational deformation,the ratio is highest under Tianjin record,medial under El Centro and lowest under Taft.As for torsion response,on average,excluding the second floor under Tianjin record,the ratio is highest under El Centro,medial under Taft and lowest under Tianjin record.Moreover,the reduction ratio of the first floor is higher than that of the second floor under the same earthquake record.