中文摘要：

提出了一种基于能力谱原理的多自由度体系延性折减系数计算方法，然后依据我国抗震规范按照不同高度、不同设防烈度设计了三组九个RC框架结构，并采用Pushover方法计算了它们的延性折减系数、超强系数和强度折减系数．发现高烈度区的结构，在相同高度下具有较低的储备强度，而在相同设防烈度下，结构越高强度储备越低．根据研究结果，指出了我国现行抗震规范下RC框架结构地震作用取值中的不足，并提出了对规范的修改建议．

英文摘要：

A method for calculating the ductility reduction factor of a muhi-degree-of-freedom system was proposed based on the capacity spectrum theory. The ductility reduction factors, overstrength factors, and strength reduction factors of 9 RC frames according to current Chinese seismic code with different heights and design seismic zones were calculated using the Pushover method. It is found that the structures with a higher design seismic level have a lower reserve strength when they have the same height, while the reserve strength will decrease with increasing height at the same design seismic level. The current Chinese seismic code was evaluated and some advices were proposed for its future modification.