【摘要】 建筑物抗震能力是抗震设计、鉴定加固和地震风险评估的基础,以往的研究大多集中于建筑物震害预测,而非着意于它们的抗震能力,更不能给出定量指标以衡量抗震能力。采用Push-over分析方法得到的能力谱进行抗震能力研究,基于性态设计的思想给出建筑物相对抗震能力的定义,建立能力谱与抗震能力指数的关系,采用定量指标评定建筑物在不同地震作用下的相对抗震能力,并获得定性的性态描述;再根据建筑物达到预期设防水平的能力给出建筑物绝对抗震能力的定义,对能力谱进行等面积双线性化形成滞回模型,建立滞回面积与建筑物绝对抗震能力的关系,可以不依赖于地震作用评估建筑物的绝对抗震能力,不仅能够比较不同建筑物抗震能力的差异,还能估计建筑物实现预期设防水平的能力。以汶川地震中一栋倒塌、一栋严重破坏的钢筋混凝土框架结构抗震能力分析为例,通过抗震能力分析结果和实际震害的对比论证了该方法的有效性。更多还原

【Abstract】 The seismic capacity of buildings is the basis of seismic design,seismic appraisal/retrofit and seismic damage assessment.Most of previous studies cannot present a quantitative index to scale the seismic capacity of buildings because the focus has been the seismic damage of buildings but not the seismic capacity.This paper presents a study on the seismic capacity using capacity spectrum and push-over analysis method.The definition of relative seismic capacity of buildings is proposed for performance-based seismic design.The relationship between capacity spectrum and seismic capacity index is established.The quantitative index is employed to scale the relative seismic capacity of buildings under different seismic actions,and the qualitative description of performance level is provided.The definition of absolute seismic capacity is proposed as the capacity of buildings reaching the seismic design level.A hysteretic model can be obtained from equal-area double-linearization of the capacity spectrum.The relationship between the hysteretic area and the absolute seismic capacity is established to assess the absolute seismic capacity without considering seismic action.The absolute seismic capacity assessment method can not only compare the difference between different buildings but also assess the capacity of buildings reaching the seismic design level.Two case studies of seismic capacity analysis are presented,one collapsed and the other seriously damaged reinforced concrete frame structures in the M8.0 Wenchuan earthquake.Comparison of the analysis results with the real seismic damages demonstrates the validity of the proposed method.更多还原