【作者】 李刚强；

【导师】 白绍良； 傅剑平；

【作者基本信息】 重庆大学 ， 结构工程， 2006， 硕士

【摘要】 各国现行抗震设计规范采用的居于主导地位的抗震设计方法仍然是基于弹性反应谱理论和R-μ基本准则的通用抗震设计方法。其中,通过地震力降低系数R把基准设防地震作用降到设计采用的相对偏低的地震作用水准,同时通过相应的能力设计措施力求保证结构在强震下的反应需求不超过结构的反应能力。但最近完成修订的美国抗震设计规范IBC 2003和加拿大抗震设计规范NBCC 2005已展示出为了追求等倒塌风险而把基准设防地震作用水准从475年重现期水准提高到预期最大地震水准的动向,从而使各类超静定结构对应这一地震水准的R-μ规律及超强特征成为理应进一步深入揭示的结构抗震性能规律。为此,本论文初步完成了以下研究工作:①对迄今为止已完成的单自由度非弹性体系R -μ-T规律主要研究成果的归纳和分析;②对迄今为止已完成的多次超静定非弹性结构R -μ规律及超强特征主要研究成果的归纳和初步评述;③对各国抗震设计规范反映R -μ规律及超强等问题的具体做法进行归纳和对比分析;④利用动力推覆分析初步完成了对我国五个不同设防分区各一榀典型框架的结构超强特征分析,并对分析结果进行了讨论。从上述研究工作中得出的主要结论是:①从单自由度和多自由度非弹性体系R -μ规律的主要研究成果来看,各研究者所得主要规律和认识趋同。应该承认R-μ基本准则是保证结构抗震性能的基本准则,在设计地震作用参与荷载组合对结构设计起控制作用时必须遵循。中国现行规范不符合R-μ基本准则的缺口急待修补。②若以预期最大地震水准作为基准设防地震水准,则实际结构地震力降低系数R可能应至少包含两个因素,即考虑结构延性能力的延性降低系数Rμ和考虑整体结构超强效应的结构超强系数? d。③本文动力推覆分析识别出0.1g区、0.15g区、0.2g区、0.3g区和0.4g区典型框架相对保守的超强分别为3.15、2.32、1.83、1.54和1.79;同时清楚的识别出0.15g区、0.2g区、0.3g区典型框架存在相对较高的形成层侧移机构的风险。④美国IBC 2003和加拿大NBCC 2005为了追求等倒塌风险把基准设防地震作用水准提高到了预期最大地震水准;美国IBC 2003、加拿大NBCC 2005和新西兰NZS 4203(1992)为了更好的考虑不同地区地震危险性特征的差异,采用一致风险更多还原

【Abstract】 The dominant seismic design method in current seismic design codes of different countries is still the conventional seismic design method based on elastic response spectra theory and R-μprinciple. In this method, the reference earthquake design level is reduced to relatively lower earthquake level adopted by design through force reduction factor R, and the corresponding capacity design measures are adopted to ensure the response demand of structures under strong earthquakes doesn’t exceed the response capacity.However, the recently revised seismic design codes IBC 2003 of USA and NBCC 2005 of Canada reveal a trend of increasing reference earthquake design level from earthquake level with a recurrence period of 475 years to anticipated maximum earthquake level so as to provide a more uniform margin against collapse. This makes that R-μrelations and overstrength character of redundant structures corresponding to anticipated maximum earthquake level should be further studied.Therefore, the main research work finished preliminarily in this thesis is as follows:①Summary and analysis of the chief research findings of R-μ-T relations for single-degree-of-freedom inelastic systems so far finished.②Summary and commentary of the main research findings of R-μrelations and overstrength character of redundant structures.③Summary and comparison of specific measures reflecting R-μprinciple and overstrength character in seismic design codes of different countries.④Overstrength character analysis of five typical frames, which separately locate in intensity zonation 0.1g, 0.15g, 0.2g, 0.3g and 0.4g, through dynamic pushover analysis, and discussions of the analysis results.From the research work stated above, the main conclusions can be drawn as follows:①The main research findings of R-μrelations of single-degree-of-freedom and multi-degree-of-freedom inelastic systems are consistent. It should be admitted that R-μprinciple is the fundamental principle to ensure seismic performance of structures and must be followed when load combinations including earthquake action control the design of structures. The flaw of current Chinese codes which is inconsistent with R-μprinciple is pressing for remedy.②If the anticipated maximum earthquake level are determined as reference earthquake design level, the force reduction factor R of actual structures may include at更多还原