【摘要】 合理选取4类场地320条强震记录,研究地震动特性和恢复力模型动力参数对弹塑性SDOF体系的地震能量响应及其分配规律的影响,得到如下结论:1对于弹塑性SDOF体系,只要给出某一标准设防烈度的地震能量反应谱,其他设防烈度的能量反应谱可以根据PGA设防烈度与PGA标准烈度比值的平方调整得到;2可忽略屈服后刚度比对结构地震能量响应及其分配规律的影响;3阻尼比对地震总输入能的影响不大,但却对阻尼和滞回耗能有较大影响;4弹性和弹塑性SDOF体系的地震总输入能存在一定差别的,不能忽略结构延性对地震总输入能的影响;5低延性结构的延性能力的增加将会大幅提高其滞回耗能能力。在此基础上,采用非线性能量反应时程分析方法,建立适用于我国梁式桥抗震设计的地震总输入能谱、能量折减系数谱、滞回耗能谱和滞回耗能比谱,并为梁式桥基于能量的抗震设计提供以下建议:在采用能量方法对梁式桥进行抗震设计,因尽量使结构周期超过临界周期,以避免结构弹塑性地震输入总能量被放大;同时,还应控制梁式桥的延性不宜过大或过小。更多还原

【Abstract】 320 strong motion records of four sites are selected. Seismic energy response of elastic-plastic SDOF system is studied by considering characteristics of earthquake motion and dynamic parameters of restoring model. Following results are obtained: 1 Seismic energy spectra of other protected earthquake intensity can be obtained by adjusting the seismic energy spectra of the standard protected earthquake intensity according to the square ratio of PGA( protected earthquake intensity) to PGA( standard protected earthquake). 2 Seismic energy response is not affected by yielding stiffness ratio. 3 Seismic input energy can not be affected by the damping ratio. On the contrary,hysteretic and damping energy dissipation are affected obviously by the damping ratio. 4 The seismic input energy of elastic and elastic-plastic system is different. And the effects of ductility on seismic input energy can not be neglected. 5 Hysteretic ability of low ductile structure can be greatly increased by increasing the ductility. By nonlinear seismic energy analysis method,elasticplastic dynamic analysis program is used to establish seismic input energy spectra,reduced energy spectra,hysteretic energy dissipation spectra and hysteretic energy dissipation ratio spectra. When energy concept is used in seismic design for bridge,structure designed period should be to be under the critical period to avoid the amplification of seismic input energy. Meanwhile,the ductility of bridges should also be controlled.更多还原