摘要
针对地震动频谱特性的描述方法及频谱特性与结构损伤的相关关系进行了研究。提出了Fourier谱强度频率匹配度、结构振型频率影响系数和类共振放大系数的概念及计算公式;以基础隔震结构作为弹塑性时程分析模型,计算结构整体损伤指数;最后,分别从卓越频率、三大峰值频率和平均频率三个角度研究地震动频谱特性与结构损伤的相关性。研究结果表明:地震动频谱特性对结构造成的损伤与结构各阶振型频率有关,且第一振型频率影响最大;Fourier谱强度频率匹配度越大,表明结构发生类共振的概率越大,造成隔震层和上部结构的损伤也越大;类共振放大系数反映频谱特性对结构造成损伤的程度,平均频率类共振放大系数与结构损伤的相关性最好,用平均频率能够较好地描述地震动的频谱特性。
The spectral characteristics of ground motion and the correlation between spectral characteristics and structural damage were studied.The concept and calculation formula were proposed for the frequency matching degree of Fourier spectral intensity,structural modal frequency influence coefficient and magnification factor of pseudo-resonance.A base-isolated structure model for elasticplastic history analysis was established and used to calculate the structure overall damage index.The correlation between the spectral characteristics and structure damage was studied in regard to the dominant frequency,three major peak frequencies and average frequency.The results show that the structural damage caused due to spectral characteristics is related to the modal frequency of the structure,and the influence of the first modal frequency is the most significant.The greater the frequency matching degree of Fourier spectral intensity,the greater the possibility of structure pseudoresonance and the greater the damage index of the isolation layer and the upper structure.The magnification factor of pseudo-resonance reflects the damage degree of the structure caused due to spectral characteristics.It is also found that the average frequency is rather good to represent the spectral characteristics of ground motion.
作者
杜永峰
王亚龙
李虎
方登甲
时晨
DU Yongfeng;WANG Yalong;LI Hu;FANG Dengjia;SHI Chen(Institute of Earthquake Protection and Disaster Mitigation,Lanzhou University of Technology,Lanzhou 730050,China;Western Center of Disaster Mitigation in Civil Engineering of Ministry of Education,Lanzhou University of Techology,Lanzhou 730050,China)
出处
《振动与冲击》
EI
CSCD
北大核心
2019年第10期156-161,184,共7页
Journal of Vibration and Shock
基金
国家自然科学基金(51778276
51578274)
关键词
平均频率
振型频率
频谱特性
损伤指数
Fourier谱强度频率匹配度
类共振放大系数
average frequency
modal frequency
spectral characteristics
damage index
frequencymatching degree of Fourier spectral intensity
magnification factor of pseudo-resonance
