在隔震层安装金属屈服阻尼器可以有效控制隔震层在地震下的位移。由于隔震层在地震下产生多向变形，因此要求安装在隔震层中的金属屈服阻尼器需具有多向的变形能力。既往研究表明 U 型金属屈服阻尼器在面内具有良好的耗能能力，对于提高结构阻尼比，控制隔震结构的位移具有非常显著的作用。然而关于其面外性能的深入研究尚未见报道。提出了开槽 U 型阻尼器以提高其面外性能，并通过拟静力试验考察了阻尼器宽度，高度，以及长度对其面外性能的影响，实验表明合理设计的开槽 U 型阻尼器具有良好的耗能能力和低周疲劳性能。同时采用有限元方法补充了试件的数量，进行了参数分析。根据参数分析的结果提出了开槽型 U 型金属屈服阻尼器的屈服位移，屈服恢复力设计公式。另一方面，根据虚功原理提出了开槽 U 型阻尼器的极限恢复力计算公式，并通过试验结果与有限元模型的计算结果校对了该公式的精度和适用范围。%Metal dampers installed in base isolation layers are effective to control the displacement of the base isolation layers under earthquakes.The base-isolation layers deform in multiple directions during an earthquake,requiring that the dampers should also have multi-directional deformation capacity.Previous studies suggest the U-shaped steel dampers which have satisfactory deformation and energy dissipation capacity in-plane,and can significantly increase the damping of the structures and control the displacement of the base isolation layers.However,the out-of-plane behaviours of the U-shaped steel dampers are not necessarily satisfactory.To this end,a new type of slotted U-shaped steel damper was proposed to improve the out-of-plane performances of the U-shaped steel damper.The effects of the damper width, height,and length on the damper performances were investigated by using quasi-static tests.The test results indicate that the U-shaped steel damper with appropriate design parameters has satisfactory energy dissipation capacity and low cycle fatigue behaviour.The formulation is accurate for the estimation of damper strength.Parametric finite element analysis was conducted to supplement the test results.Based on the results of parametric analysis,the formulas for yield displacement and restoring force of the slotted U-shaped damper were derived by using regression analysis.The formula to estimate the dampers ultimate restoring forces was also derived based on the virtual work principle.The accuracies and application conditions of the formulas proposed were investigated according to the results of experiment and numerical analysis.
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