【摘要】 在对Modal Pushover方法的原理及误差进行评价的基础上,结合与整体目标位移延性系数相对应的钢筋混凝土框架构件刚度折减系数的合理取值,提出了Modal Pushover的改进方法。为考察高阶振型参与程度的影响规律,以10层和16层钢筋混凝土平面框架为例,将框架在7条地震动波不同峰值加速度作用下的非线性地震反应统计结果作为对比基准点,研究ModalPushover方法、改进Modal Pushover方法的分析结果随框架周期、地震动强度增加的误差变化规律。研究表明,Modal Pushover方法、改进Modal Pushover方法的误差并不随着框架周期加大而增加,表明该方法能合理地考虑高振型参与反应的影响;框架非线性程度加深后,改进ModalPushover方法可在一定程度上降低MPA(Model Pushover Analysi)方法的误差。更多还原

【Abstract】 Based on evaluation of the basic principle and error of the modal pushover analysis method,an improved method is suggested by selecting rational values of stiffness reduction parameters of beams and columns in a reinforced concrete frame corresponding to the global target displacement ductility ratio.A 10-story and a 16-story reinforced concrete plane frame are designed as examples to investigate the influence of higher modes.Nonlinear seismic responses of the two frames under excitations of seven earthquake waves of varying earthquake intensities are selected to be the reference points for a comparison study.The changing rules of the results of modal pushover analysis and modified modal pushover analysis with respect to various natural fundamental periods and different earthquake intensities are studied.Research results show that the error of modal pushover analysis and modified modal pushover analysis will not increase with a larger fundamental period,which implies that modal pushover analysis can cover the effect of higher modes reasonably.When the degree of nonlinearity of the structure is more severe,the modified modal pushover analysis we suggest could decrease the error of normal modal pushover analysis to a certain extent.更多还原