弹塑性钢阻尼器用于大跨度CFST拱桥的减震控制研究

Seismic response control of a long-span CFST arch bridge with EPSDs

弹塑性钢阻尼器具有良好的减震效果,但目前的研究和应用主要集中在房建领域。以主跨368m的茅草街大桥为研究对象,进行了弹塑性钢阻尼器用于大跨度钢管混凝土拱桥地震响应的减震控制研究,采用非线性时程分析法进行了阻尼器关键参数的敏感性分析,研究了不同屈服荷载、不同弹性刚度及不同空间布设阻尼器的减震效果,最后重点分析了行波效应对弹塑性钢阻尼器减震效果的影响。结果表明,对于该中承式钢管混凝土系杆拱桥,弹塑性钢阻尼器的减震效果明显;综合考虑各部位的地震响应,在主梁各支承间均匀布设阻尼器为最佳布置方式;考虑行波效应后,阻尼器的减震效果更佳。

Elastic-plastic steel damper （EPSD） has a good seismic response control effect, but the current studies and applications of this type of damper are mainly concentrated on building structures. Maochaojie bridge, a concrete- filled steel tubular （CFST） arch bridge, with a main span of 358m was taken as an example here. The control effect of elastic-plastic steel dampers on the seismic response of the bridge was investigated. The parametric sensitivity of dampers was calculated based on the nonlinear time-history analysis. The parameters included yield loads, elastic stiffness and different spatial locations of dampers. The influence of traveling wave effect on the control efficiency of EPSD was especially investigated at last. Results showed that the control effect of EPSD is prominent for the long span CFST arch bridge ; evenly distributing dampers among bearings of girder is the optimal arrangement when all seismic responses of key places are considered; the control effect of EPSDs is more obvious after considering traveling wave effect.