设备抗震鉴定中混凝土支撑对地震输入影响研究

Effect of Concrete Surpport on Seismic Input in Equipment Seismic Qualification

在有混凝土支撑结构的设备的抗震鉴定中,对于没有专门计算混凝土支撑处的地震输入的设备的状况,选择设备的上一楼层响应谱直接作为设备地震载荷输入,是目前较为常见的一种做法。本文将有支撑设备简化为两自由度弹簧-质量模型,将无支撑设备简化为单自由度弹簧-质量模型,通过对比2个模型的响应特性,分析支撑结构对设备加速度响应的影响。从理论上验证了选择设备上一楼层响应谱直接作为设备地震载荷输入的做法存在不保守性。

In the seismic qualification of the equipment with concrete support,the response spectra of the upper floor of the equipment are adopted when the seismic inputs at the supporting points are not available.In this paper,the equipment with supports is simplified as the spring-mass model of two degrees of freedom,and the equipment without supports is simplified as the spring-mass model of one degree of freedom.By comparing the characteristics of the acceleration responses of the two models,the effects of supports on the characteristics of the responses of equipment are analyzed.It is found that the seismic input using the upper floor response spectra to seismically qualify the equipment is underestimated by theory and finite element analysis.