【摘要】 非线性反应谱是基于性能抗震设计理论中亟待解决的基础性课题之一。Ay-Dy格式地震需求谱的特点是,过原点的射线与不同屈服强度系数的需求谱曲线相交,各个交点对应的周期都相同,从而为在结构基于位移抗震设计方法中实现多级性能目标提供方便。本文将4种场地类别上的434条地震记录,按《高架桥梁抗震设计》场地类别和地震动特征周期分区的要求分为12组,通过对单自由度体系的时程分析,得到基于场地类别和地震动特征周期分区的Ay-Dy格式地震需求谱;研究结构强度水平、周期、场地类别及地震动特征周期分区等因素对需求谱的影响;通过非线性回归分析得到不同场地类别、不同特征周期分区和不同强度水平下的回归表达式,可用于结构非线性位移的解析计算。最后,通过算例说明运用本文成果进行设计的过程,并与已有文献结果比较,证明本文研究的正确性。更多还原

【Abstract】 The nonlinear response spectrum is one of the fundamental subjects to be solved in performance-based seismic design.The inelastic seismic demand spectrum with the yield spectral acceleration-yield displacements format has the advantage that structural periods corresponding to intersection between radial lines and demand spectrum curves with different yield strength factors are all the same and this provides convenience to realize multiple-level anti-seismic objectives in displacement-based seismic design.In this paper,434 earthquake ground motion records onⅠ～Ⅳ soil sites are classified into 12 groups according to the soil conditions and ground motion characteristic periods grouping specified in Guide to seismic Design of Double Deck Viaduct.By a great deal of time history analysis of single degree of freedom,the seismic demand spectra with Ay-Dy format based on soil conditions classification and ground motion characteristic period grouping are produced.The influence of the level of strength of the structure,vibration periods,soil site classifications and ground motion characteristic periods grouping on the seismic demand spectrum is studied.By means of nonlinear regression analysis,the regression expression adaptive to different soil conditions,different ground motion characteristic period grouping and different strength levels is obtained,which can be applied in analytic calculation of nonlinear displacements of structures.An example is provided to explain the design process using the research results of this paper,and the correctness of the research results is verified by comparing to the outcome of the existing literature.更多还原