• 责任者：Zhao Guochen (Department of the Civil Engineering ; Harbin Institute of Technology ; Shandong 264209 ; China) ; Xu Longjun
• 刊名：Chinese Journal of Geophysics
• 出版年：2013
• 卷期：56(12)
• 关键词：地震动 ; ground motion
• 页码：p.4153-4163
• 图表：10 illus., 5 tables, 31 refs.
• 分类号：0500
• issnNo：ISSN0001-5733
• isbnNo：CN11-2074/P

     The near fault ground motion with long period is a special destructive ground motion. For further research on the composition of low-frequency components and their pulse characteristics, a decomposition method of ground motion components based on multi-scale analysis method in wavelet theory was proposed. Accordingly, a complete ground motion can be decomposed into multiple components with different frequencies. First, we elaborated the validity and accuracy of the decomposition method in three aspects, which are the frequency domain, time domain and the dynamic response. Second, decomposed 53 typical near-fault ground motions from 12 recent major earthquakes through this method, and obtained a total of 266 ground motion components. Third, quantitatively analyzed the variation of the long period components in near fault ground motions with the impact factors of site and rupture distance. Last, used predominant component as the simplified model of the dominant pulse, and analyzed the variation of the velocity amplitude and pulse period with magnitude, rupture distance factors. The results showthat 0.2-2 s component is the main ingredient of near-fault ground motions; There are more long-period components in soil ground motions than the rocks; In near-fault area, 0~ 15 km, with the rupture distance increasing the long period components＇ proportion decreases; PGV,,, the velocity amplitude of predominant component, is about 0. 6 times of PGV, the velocity amplitude of original ground motion, and there is a clear linear relation between them. With the rupture distance increasing PGVp decreases, and will be larger in great earthquake. The pulse period Tp increases logarithmically linearly with the moment magnitude.