Seismic response of cracking features in Jubao Mountain during the aftershocks of Jiuzhaigou Ms7.0 earthquake

doi:10.1007/s11629-019-5570-0

CORC > 成都山地灾害与环境研究所 > 中国科学院水利部成都山地灾害与环境研究所 > Journal of Mountain Science > Journal of Mountain Science-2019 > Vol16 No.11

	Seismic response of cracking features in Jubao Mountain during the aftershocks of Jiuzhaigou Ms7.0 earthquake
	Shen, Tong; Wang, Yun-sheng; Luo, Yong-hong; Xin, Cong-cong; Liu, Yong; He, Jian-xian
刊名	JOURNAL OF MOUNTAIN SCIENCE
	2019
卷号	16 期号:11 页码:2532-2547
关键词	Jiuzhaigou Ms7 0 earthquake Aftershocks Directivity effects Slope dynamic response HVSR SSR
ISSN号	1672-6316
DOI	10.1007/s11629-019-5570-0
文献子类	Article
英文摘要	Jiuzhaigou is a world-heritage site located in the plateau area of Northwest Sichuan Province, China. Serious slope failures in the epicentral area were triggered by the Ms7.0 Jiuzhaigou earthquake occurred on August 8, 2017. The source areas of the hazards are usually concentrated near ridge crests, revealing the possible occurrence of ground motion amplification phenomena. To explore the role of the amplification of ground motions in the formation of earthquake-triggered slope failures, two seismometers were installed, on the next day after the main shock, at the bottom of the slope of Jubao Mountain near the seismogenic fault. The two monitoring sites are located at elevations of 1414 m (J1) and 1551 m (J2, the top of the mountain). Five aftershocks were recorded by the monitoring instruments. We compared the mean levels of the peak ground acceleration (PGA) observed at different locations, and investigated the directional variations in the shaking energy by analyzing the polar diagrams of the Arias intensity (Ia). Then, in order to identify the directional resonance phenomenon and their frequencies and amplification coefficients, we examined the horizontal-to-vertical spectral ratio (HVSR) and the standard spectral ratio (SSR). Polar diagrams of the Arias intensity (Ia) indicated that the site response of Jubao Mountain showed a pronounced directivity (in the EW direction) with shaking maxima near the hill top oriented orthogonally to the elongation of the relief. We observed an obvious resonance phenomenon at site J2 at relatively low frequencies (2.5-9 Hz) and very weak spectral amplifications at site J1 at high frequencies (5-15 Hz), which suggested that the predominant frequency of monitoring site J2 was obviously attenuated and that the difference in the spectra was related to the influences of the local-scale site conditions of the whole mountain. The results of spectral ratio analyses (HVSR and SSR) showed that the direction of resonance was concentrated around an EW orientation, and the amplification factors near the hill top were larger than 2. It suggests that geologic factors also play a significant role in the anisotropic amplifications affecting the tops of slopes besides the topographic effects.
电子版国际标准刊号	1993-0321
语种	英语
WOS记录号	WOS:000495245200006
内容类型	期刊论文
源URL	[http://ir.imde.ac.cn/handle/131551/46611]
专题	Journal of Mountain Science_Journal of Mountain Science-2019_Vol16 No.11
推荐引用方式 GB/T 7714	Shen, Tong,Wang, Yun-sheng,Luo, Yong-hong,et al. Seismic response of cracking features in Jubao Mountain during the aftershocks of Jiuzhaigou Ms7.0 earthquake[J]. JOURNAL OF MOUNTAIN SCIENCE,2019,16(11):2532-2547.
APA	Shen, Tong,Wang, Yun-sheng,Luo, Yong-hong,Xin, Cong-cong,Liu, Yong,&He, Jian-xian.(2019).Seismic response of cracking features in Jubao Mountain during the aftershocks of Jiuzhaigou Ms7.0 earthquake.JOURNAL OF MOUNTAIN SCIENCE,16(11),2532-2547.
MLA	Shen, Tong,et al."Seismic response of cracking features in Jubao Mountain during the aftershocks of Jiuzhaigou Ms7.0 earthquake".JOURNAL OF MOUNTAIN SCIENCE 16.11(2019):2532-2547.