【摘要】 归纳了单自由度体系R-μ-T规律和多自由度体系的R-μ基本规律,指出在确定设计地震作用时,除了考虑结构延性能力的影响外,还应考虑结构超强的影响;在对比了美国、加拿大、欧盟和新西兰4国规范考虑结构超强的思路后,建议中国相关设计规范也应考虑结构超强的影响。然后对美国、加拿大、欧盟、新西兰和中国5国规范采用的基准设防地震作用水准进行了对比评述,讨论了加拿大NBCC 2005和美国IBC 2003规范采用预期最大地震作用作为基准设防地震作用的合理性。还强调了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的荷载组合对结构设计起控制作用时必须遵循,而中国现行规范有关条文不符合R-μ基本准则的缺口急待修补。更多还原

【Abstract】 The R-μ-T principle of single-degree-of-freedom(SODF) systems and the R-μ principle of multi-degree-of-freedom(MODF) systems are summarized.The influences of structural overstrength as well as the ductility capacity of structures should be considered in the determining of the earthquake design level.After the comparison of the considerations of structural overstrength in the codes of U.S.A,Canada,Europe,and New Zealand,it is proposed that the influences of structural overstrength should be included in relating provisions in Chinese Code.Then the reference earthquake design levels adopted by the cods in U.S.A,Canada,Europe,New Zealand,and China were compared and commented,and the rationality of the anticipated maximum earthquakes adopted as reference earthquake design levels in NBCC 2005 and IBC 2003 is discussed.Moreover it is emphasized that the R-μ principle is the basic rule for ensuring the seismic performance of structures,to which should be complied when the designs of structures are controlled by the loading combinations with participation of earthquake actions.Therefore the gap incompatible with the basic R-μ principle in relating provisions in Chinese Code should be bridged urgently.更多还原