SMA自复位隔震桥梁基于位移的抗震设计方法

Displacement- based design approach for highway bridges with SMA isolators

本文针对隔震桥梁结构的抗震设计方法展开研究。首先对隔震桥梁结构进行模型简化,得到可用于设计的精简模型,并通过合理的构造设计,得到可实用的SMA隔震层;经过推导得到简化模型的等效延性和刚度;在非线性反应谱的基础上,建立直接基于位移的抗震设计方法;最后通过数值模拟分析对设计方法进行验证,结果显示在设计地震作用下,桥梁的地震反应与预期的设计指标相差很小,说明该位移设计方法具有较好的可靠性。

In this paper, the seismic design method applied to SMA isolated bridge has been developed. The isola- ted bridge with SMA isolators has been simplified to a simple model which can be used in the design process. And the SMA isolation layer has been designed in detail for which can be used in practice. The efficiency ductility and effective stiffness of the simplified model was deduced. A displacement-based design approach for bridges with SMA isolators was proposed based on the nonlinear response spectra. The efficacy of the displacement-based design ap- proach is validated by numerical simulations, and the results indicate a properly designed bridge using the proposed approach can achieve the prescribed performance objectives.