摘要
对于基础隔震结构而言,其上部结构和隔震层的阻尼特性截然不同,往往呈现出明显的非比例阻尼特性。因此,有必要建立一种考虑非比例阻尼的隔震结构实用计算方法以便于推广和应用。通过用双自由度振动体系模拟基础隔震结构,在建立运动方程时考虑其非比例阻尼效应。通过对该简化模型进行动力时程分析,得到其在近场及远场地震记录作用下考虑非比例阻尼与瑞利阻尼的反应谱,并通过曲线拟合得到了非比例阻尼反应谱和瑞利阻尼反应谱的谱比值与结构自振周期之间的关系式。然后对某实际隔震工程进行地震响应分析,验证所提公式的合理性。
The damping characteristics of upper structure and isolation layer for a base-isolated system are completely different,so the system often exhibits significant non-proportional damping characteristics. It is necessary to consider the non-proportional damping during aseismic design of base-isolated structures. Meanwhile,this design method is convenient for promotion and application. Here,a 2-DOF simplified model for base-isolated structures was set up,and the non-proportional damping effect was considered to establish the dynamic equation of the system. Then,the responses of the simplified model were analyzed and its response spectra considering non-proportional damping and Rayleigh damping,respectively under the excitation of near-field and far-field ground motions. The calculation formulas for the ratio of its non-proportional damping response spectra to its Rayleigh damping ones and the system＇s natural vibration periods were deduced wth the curve-fitting method. Finally,the seismic response analysis for a real base-isolated structure was performed,and the reasonableness of the proposed formulas.
出处
《振动与冲击》
EI
CSCD
北大核心
2016年第17期207-212,共6页
Journal of Vibration and Shock
基金
国家自然科学基金资助项目(51178211)
关键词
非比例阻尼
反应谱
近远场地震记录
基础隔震结构
non-proportional damping
response spectra
near-filed and far-filed ground motion records
base-isolated structure
