Site characteristic parameters’ quick measurement based on micro-tremor’s H/V spectra
LIU Yushi1、2,SHI Lijing1
1. Institute of Engineering Mechanics, China Earthquake Administration, Harbin 150050, China;
2. Sichuan Center of Patent Examination Cooperation, the Patent Office of SIPO, Chengdu 610213, China
Abstract：Micro-tremors at 37 sites were observed and measured. Correlations among the micro-tremor H/V spectra predominant frequency and site characteristic parameters including thickness of sediment, equivalent shear wave velocities in different depths, and site period were studied. Comparing these correlations and the study results of ground motion H/V spectra in different regions, the feasibility and accuracy of using the micro-tremor H/V spectra method to quickly measure site characteristic parameters were explored. Results showed that the predominant frequency of micro-tremor H/V has a strong correlation with the thickness of sediment, if using the micro-tremor H/V spectra method to measure thicknesses of sediment in different regions, their relative differences within a frequency range of 1~2Hz are less than 15%, the relative differences increase beyond this frequency range; the predominant period of the micro-tremor H/V spectra is almost the same as the site sediment equivalent period; when the micro-tremor H/V spectra’s predominant period >0.5s, the site’s equivalent shear wave velocities Vs20 and Vs30 as well as equivalent periods Ts20 and Ts30 have little changes, they have average values of 200m/s，250m/s，0.8s and 0.6s, respectively.
刘宇实1、2，师黎静1. 基于地脉动谱比法的场地特征参数快速测定[J]. 振动与冲击, 2018, 37(13): 235-242.
LIU Yushi1、2,SHI Lijing1. Site characteristic parameters’ quick measurement based on micro-tremor’s H/V spectra. JOURNAL OF VIBRATION AND SHOCK, 2018, 37(13): 235-242.
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