基于《电力设施抗震设计规范》的地震动随机模型参数研究

依据《电力设施抗震设计规范》(GB50260-96)中的设计反应谱,对随机地震动功率谱参数的取值进行了具体研究。首先,采用时间包络函数考虑地震的非平稳特性,给出了地震动持时的取值;然后,根据加速度峰值等效原则,迭代计算得到地面的加速度功率谱密度曲线;最后,选定Clough-Penzien修正过滤白噪声模型作为拟合函数,通过非线性拟合技术拟合了与《规范》中的地震烈度、场地类别相对应的谱参数。研究结果表明,Clough-Penzien修正过滤白噪声模型能较好地拟合其曲线形状。本文给出了相对于规范中的地面加速度功率谱参数值,可供这种模型作为地震地面运动输入时选用。

Parameter Study on Seismic Random Model Based on Code for Design of Seismic of Electrical Installations

The spectral parameters of a seismic random model have been studied on the basis of the design response spectrum in the Chinese standard Code for design of seismic of electrical Installations (GB50260-96). First, the nonstationarity of the ground motion is represented with an envelope function, which de-fines the duration of the ground motion at same time. Then, the power spectral density (PSD) of the acce-leration at ground level is evaluated by an iterative approach according to the principle of equivalent peak acceleration. Finally, the Clough-Penzien acceleration spectrum is selected as a target function to calculate the PSD curve through nonlinear fitting on the parameters, such as earthquake intensity and site type, defined in the code. The results show that the Clough-Penzien spectrum can fit the PSD curve well. The spectrum parameters of the random model of ground motion are given in this paper, and they provide a re-ference for the selection of ground motion input.