弹塑性钢阻尼器对中等跨径斜拉桥横桥向减震效果的振动台试验研究

SHAKING TABLE TEST OF TRANSVERSE SEISMIC RESPONSE REDUCTION OF MEDIUM-SPAN CABLE-STAYED BRIDGES USING YIELDING STEEL DAMPERS

为了研究弹塑性钢阻尼器对中等跨径斜拉桥横桥向的减震效果,该文以某一典型中等跨径混凝土斜拉桥为研究对象,设计了1/20全桥试验模型,通过改变塔梁、墩梁横桥向的连接方式,建立了固结体系和采用弹塑性钢阻尼器的减震体系两种试验模型,采用Chi-Chi波和场地人工波进行了横桥向四台阵全桥振动台试验。试验结果表明:相对于固结体系而言,横桥向采用弹塑性钢阻尼器的减震体系利用弹塑性钢阻尼器良好的滞回耗能性能,可以有效地减小塔顶位移和塔底应变,具有良好的减震效果,是合理的抗震体系之一。

To investigate transverse seismic response reduction of medium-span cable-stayed bridges using yielding steel dampers, a 1/20-scale full bridge model of a typical medium-span concrete cable-stayed bridge was designed, constructed and tested on the shaking tables at Tongji University, Shanghai, China. Chi-Chi wave and site specific artificial wave were input in the transverse direction. In this test, two types of transverse seismic structural systems were considered, including fixed system and energy dissipation system with yielding steel dampers. The test results show that the seismic performance of the bridge with yielding steel dampers can significantly reduce the strains at the bottom of the tower legs and the displacement at the tower top. Therefore, the proposed energy dissipation system can be applied to the cable-stayed bridges to achieve better seismic performance.