【摘要】：為了給長周期地震動的選取和評價提供依據(jù)及量化指標,利用Hilbert-Huang變換理論分析地震動能量特性,提出評價地震動周期特性的方法;并且對典型的常規(guī)地震動和近、遠場長周期地震動的時域、頻譜分布、地震動放大系數(shù)譜及周期特性進行了分析,得到了近遠場長周期地震動的時頻域特性及其與常規(guī)地震動的差異。在此基礎(chǔ)上,提出用β譜曲線2到10s譜值和周期的平方加權(quán)平均值βl作為長周期地震動的界定參數(shù);根據(jù)178條近場地震動和151條遠場地震動的βl值的統(tǒng)計分析結(jié)果提出:βl0.4的地震動為長周期地震動,βl0.2的地震動為短周期地震動(即常規(guī)地震動),0.2≤βl≤0.4的地震動為中長周期地震動。這將為柔性橋梁抗震分析時長周期地震動的選取提供依據(jù)。
[Abstract]:In order to provide the basis and quantitative index for the selection and evaluation of long-period ground motion, the energy characteristics of ground motion are analyzed by using Hilbert-Huang transform theory, and a method to evaluate the periodic characteristics of ground motion is put forward, and for typical conventional ground motion and near ground motion, The time-domain, spectral distribution, magnification factor spectrum and periodic characteristics of long-period far-field ground motions are analyzed, and the time-frequency characteristics of long-period near-far-field ground motions and their differences with conventional ground motions are obtained. On the basis of this, it is proposed that the 尾 -spectrum curve from 2 to 10 s and the squared weighted mean 尾 _ l of the period be used as the defining parameters of the long-period ground motion. Based on the statistical analysis of the 尾 _ l values of 178 near-field ground motions and 151 far-field ground motions, it is proposed that the ground motions of 尾 _ l _ 0.4 are long-period ground motions, and that of 尾 _ l _ 0.2 are short periodic ground motions (i.e. conventional ground motions) and that of 尾 _ l _ (0.4) 鈮，

本文編號：2241785