考虑场地条件与设计地震分组的输入能量谱研究

A study on input energy spectrum in consideration of site effect and design earthquake classification

建立简单适用的设计输入能量谱是将能量方法应用于实际工程设计及校核的前提.选择了Ⅰ类、Ⅱ类和Ⅲ类场地共694条水平地震动记录,分析了不同的场地类别和设计地震分组下输入能量谱的特点.通过12个不同地震动参数与能量谱值的相关性分析,得到了表征地震动输入能量的地震动参数.基于我国现行规范规定的设防烈度和设防水准,提出了地震分组指标,并建立了相应的阻尼比为5%的弹性单自由度体系设计输入能量谱,为应用能量设计法及选择地面运动输入奠定了基础并提出相关建议.

Establishing a simplified applicable design input energy spectrum is the basis of applying the energy method to practical engineering design and verification. This paper has chosen 694 horizontal seismic records on class I, II and Ill sites, and analyzed energy spectrum with different classification of design earthquakes and site classes. The correlation between 12 different ground mo- tion parameters and the energy spectrum is examined, and a ground motion parameter among them having strong relation with ground motion input energy is selected. Based on the provisions of fortification intensity and security standard in the present code, a new parameter of classification of design earthquake is put forward and the corresponding design input energy spectrum for damping ratio of 5~ of the elastic single degree of freedom system is built. Furthermore,some valuable recommendations for using the energy-based design method and selection of input ground motion are proposed.