隔震支座沿曲面布置的隔震结构动力响应及振动台试验研究

针对超设计基准地震作用下隔震层存在过大变形、影响结构安全等问题,基于已提出的一种隔震支座沿曲面布置的隔震结构,通过变形和受力分析建立了简化双自由度动力模型,得到了系统关键动力参数,即公转频率、自转频率及单摆频率等的计算式.进一步给出了结构响应传递函数,明确了结构高宽比、曲面角度、隔震层阻尼比对结构响应的影响规律,并基于...

Study on dynamic response and shaking table test of isolated structure with isolation bearings arranged along curved surface

In view of the problem that there is a risk of excessive deformation of the isolation layer under the excitation of beyond-design-basis earthquake, which affects the safety of the structure, based on a type of existing curved seismic isolated structure (CSIS) with isolation bearings arranged along curved surface, through the analysis of deformation and force, a simplified two-degree-of-freedom dynamic model was established. The calculation formulas of the key dynamic parameters of the system, i.e. revolution frequency, rotation frequency, and single pendulum frequency, were obtained. Furthermore, the transfer function of structural response was given, and the influence rules of aspect ratio, surface angle, and damping ratio of isolation layer on structural response were clarified. And the optimized parameter range of isolation layer is determined based on parameter analysis.The shaking table tests of the steel frame models with the surface angles of 0°, 4°, and 8° were completed, and the influence of the parameters of the surface isolation layer on the seismic response of the structure was clarified. The results show that the hysteretic curves of the bearings of the CSIS are plumper compared with the plane isolation structure. With the increase of the surface angle, the acceleration of the superstructure increases, and the displacement of the isolation layer decreases. The acceleration of the curved isolation structure slightly increases, but the horizontal displacement of the isolation layer significantly decreases. Under the input peak ground acceleration of 0.3g, the displacement of the isolation layer is reduced by 30%-40%. The displacement of the curved isolated structure can be significantly controlled by properly reducing the acceleration of the isolation layer.