新型自复位钢桁架梁的设计及参数分析

针对设置于不同部位、不同类型耗能元件的新型自复位钢桁架梁,理论推导了设置蝶形软钢阻尼器时,梁端对应于恢复力曲线特征点处的刚度和临界弯矩计算公式。在对比分析蝶形软钢阻尼器和防屈曲消能杆的自复位钢桁架梁抗弯刚度和耗能能力的基础上,确定了设置防屈曲消能杆的自复位钢桁架为较优结构方案。以预应力筋面积和初始应力、SC参数作为评价自复位钢桁架梁自复位性能和耗能能力的重要参数,通过数值分析研究了这些参数对自复位钢桁架梁抗震性能的影响规律,确定了最优参数取值范围,给出了设计方法,为该类构件的设计提供参考建议。

Design and parameter analysis for new self-centering steel truss beam

For the different position installation and different type of energy dissipation element for self-centering steel truss beam (SCSTB), the theoretical calculating formula of moment capacity and stiffness at end of beam are deducted corresponding to major points of their hysteretic curve when butterfly fuse is installed. Bending stiffness and energy dissipation capacity of SCSTB with butterfly fuse and bucking restrained energy dissipation bar are comparatively analyzed, and the plan of bucking restrained energy dissipation bar is optimal one. Area of prestressed bar, initial stress of prestressed bar, SC parameter are important parameters for evaluation of self-centering function and energy dissipation capacity; seismic behavior of SCSTB is researched by numerical analysis, on the basis of which, the range of optimum parameters is determined, and it can be used as a reference for the design of this component.