中文摘要：

强度折减系数既是基于强度的抗震设计中确定设计地震力的关键因素,又是基于性态的抗震设计理论中确定非弹性反应谱的主要依据.基于过去几十年强度折减系数的研究现状,分析总结了近场效应、多自由度体系效应、结构超强等重要因素对强度折减系数影响的研究进展,得出结论：若应用依赖于结构延性、周期及场地条件的强度折减系数模型,并合理考虑多自由度体系效应及结构超强的影响将使得抗震设计更加合理;另外,现有的强度折减系数模型并不适用于近场地区,而1999年集集地震提供的大量近场地震动为研究近场脉冲效应对强度折减系数的影响提供了前所未有的机会.

英文摘要：

The strength reduction factors are not only the key factors in determining design seismic force for force - based seismic design, but also the key parameters to derivate the inelastic response spectra for performance - based seismic design. The study on strength reduction factors due to hysteretic energy dissipation of the structures is summarized in this paper. And the development of near - fault effect, MDOF effect and structural overstrength effect on strength reduction factors are also reviewed. It is concluded that the use of ductility - , period - and site - dependent strength reduction factors, together with MDOF effect and overstrength of structure, can lead to a more rational seismic design approach. It is unsuitable to use the existing strength reduction factor expressions in near- fault areas, and the recent earthquake in Taiwan （1999, Chi -Chi） has significantly increased the amount of data available in the near - fault, which provides a unique opportunity to study near- fault effects.