高烈度震区桥梁减隔震设计分析

Analysis on Seismic Isolation Design of Bridges in High Intensity Earthquake Area

在高烈度震区的桥梁抗震设计中,相比于延性抗震设计,采用减隔震装置可以通过延长结构的自振周期和增大结构阻尼达到消耗地震能力和降低结构地震响应的目的,从而大大提高桥梁抗震性能,有着显著的经济性和震后易修复性的优点。以某8度区连续梁桥为工程背景,建立全桥三维空间有限元模型,通过非线性时程动力分析对桥梁减隔震性能进行研究,并与相应的非减隔震桥梁进行对比检验隔震效果。同时,结合动力分析结论对桥梁抗震构造措施进行精细设计,通过合理的构造设计保证减隔震装置作用的充分发挥,确保桥梁达到预期抗震性能目标。

In the seismic design of bridges in high intensity earthquake area,compared with the ductile seismic design,by extending the natural vibration period of the structure and increasing the damping of the structure,the seismic isolation deices are used to reach the goal of depleting the earthquake capacity and reducing the seismic response of structure so as to greatly improve the seismic performance of the bridge,which has the obvious advantages of economy and easy repair after earthquake.Taking a continuous beam bridge in 8-degree earthquake zone as the engineering background,a three-dimensional spatial finiteelement model of the whole bridge is established.The seismic isolation performance of bridge is studied by the nonlinear time-history dynamic analysis,and compared with the corresponding non-seismic isolation bridges,the seismic isolation effect is tested.At the same time,combined with the conclusion of dynamic analysis,the refined design is carried out for the seismic structural measures of bridge.The reasonable structure design can ensure the full play of the seismic isolation device function and ensure the bridge to achieve the expected seismic performance goal.