Assessment of structural response modification factors of RC frames based on capacity-demand ratio
CUI Shuangshuang1,2, SUN Hao1, CHEN Weihong3, HAN Xu1, SONG Pengyan4
1.School of Civil Engineering,Fujian University of Technology, Fuzhou 350118,China;
2.Key Laboratory of Underground Engineering in Fujian Province, Fuzhou 350118,China;
3.School of Civil Engineering, Fuzhou Universty, Fuzhou 350108,China;
4.School of Civil Engineering,Hebei University, Baoding 071002, China
Abstract：Structural response modification factor implied in our country’s current aseismic design code is a constant R≈3.0.Here, to assess whether or not the chosen value of structural response modification factor for RC frames be reasonable, a capacity-demand ratio λ was introduced.17 RC frames with different stories and fortification intensities were designed according to our country’s current aseismic design code.Based on the finite element platform OpenSees,Pushover analysis method was used to analyze these frames’ structural anti-collapse capacities, and obtain capacity values of their structural response modification factors under critical collapse state.The static capacity spectrum method and dynamic capacity spectrum one were used to analyze structure’s demand under rarely occurred earthquake, and obtain demand values and variation laws of structural response modification factors.Then, the capacity-demand ratios λ was obtained, and it was shown that its value always is larger than 1.The results showed that RC frames designed can satisfy the expected safety performance objective against collapse under rarely occurred earthquake;response modification factors of structures designed according to 8° fortification intensity are more reasonable, while those of structures designed according to 7° fortification intensity are more conservative;those of structures designed according to 6° fortification intensity are too conservative, and they can be safely increased.
崔双双1,2，孙浩1，陈伟宏3，韩旭1，宋鹏彦4. 基于能力需求比的RC框架结构反应修正系数评定[J]. 振动与冲击, 2020, 39(6): 271-276.
CUI Shuangshuang1,2, SUN Hao1, CHEN Weihong3, HAN Xu1, SONG Pengyan4. Assessment of structural response modification factors of RC frames based on capacity-demand ratio. JOURNAL OF VIBRATION AND SHOCK, 2020, 39(6): 271-276.
