摘要
本文在归纳整理国内外单自由度非弹性体系R-μ-T规律的研究成果和多自由度非弹性体系R-μ规律研究成果的基础上,强调了在建筑结构传统抗震设计方法中选择合适的地震力降低系数R和严格程度与其对应的抗震措施是在抗震设计中实现设防目标,特别是实现强震下性态控制的核心手段。在就这一核心手段对各国抗震设计规范进行对比后发现,国外规范无一例外地遵循了R-μ基本准则,只有我国建筑抗震设计多年来采用相同的R值,但抗震措施从9度区到7度区逐级下降,不符合R-μ基本准则的设计手法。已完成的严格按照我国规范要求设计的典型钢筋混凝土框架结构的多波输入非弹性动力分析初步证实,由于采用这种与R-μ基本准则不符的设计手法,我国钢筋混凝土建筑结构的抗震能力与其所在烈度区的抗震需求相比从9度区到7度0.15 g区逐级下降。这一问题应引起国内学术界和设计界的重视、研究和讨论。
Based on the main research findings of R-μ-T relations for single-degree-of-freedom systems and multi-degree-of-freedom systems, this paper emphasizes that it's the key measure to determine proper force reduction factor R with matching seismic fortification measures for the realization of performance objectives under earthquakes at various levels, especially performance control under strong earthquakes. After comparison among seismic design codes of different countries, it is obvious that all the influential foreign seismic design codes follow the "R-μ principle" ; however, Chinese seismic design codes adopt fixed force reduction factor R with more and more relaxed seismic fortification measures for regions from intensity 9 to intensity 7. The completed inelastic dynamic analysis of series of typical structures designed according to GB50011-2001 under certain ground motions reveals that the ratios of seismic capacity to seismic demand tend to decrease from intensity 9 to intensity 7 (0.15 g). This issue should be paid more attention and would cause further study and discussion in the Chinese academic and engineering design circles.
出处
《地震工程与工程振动》
CSCD
北大核心
2006年第5期144-151,共8页
Earthquake Engineering and Engineering Dynamics
基金
国家自然科学基金面上项目(59878056)
关键词
R-μ-T关系
R-μ基本准则
抗震措施
性态控制
R-μ-T relations
R-μ principle"
seismic fortification measures
performance control