Quantitative analysis on the difference of spectral ratios between offshore and onshore ground motions
TAN Jingyang1, 2， HU Jinjun1, 2， ZHOU Xutong1,2， YANG Zexi1,2
1.Institute of Engineering Mechanics, China Earthquake Administration, Harbin 150080, China;
2.Key Laboratory of Earthquake Engineering and Engineering Vibration, China Earthquake Administration, Harbin 150080, China
Abstract：To study the difference of the statistical characteristics of response spectrums between offshore and onshore ground motions, 922 sets of offshore records of K-net and 4 599 sets of onshore records of KiK-net in the Sagami Bay region in Japan were selected.The comparison and analysis of the standardized elastic response spectra and the elastoplastic response spectra of the offshore and onshore ground motions show that: the coefficients of variation of averaged response spectra are small, it is reasonable to take the average value as a quantitative comparable parameter.When the spectral period is less than 0.5 s, the difference between the response spectra of offshore and onshore ground motions is rather small.When the period is longer than 0.5 s, the difference is obvious, and the vertical component of the offshore ground motion is significantly smaller.For the constant-strength ductility spectra, when the seismic magnitude or epicentral distance is small, it is necessary to consider the difference between the horizontal components of offshore and onshore ground motions with spectral period above 1.5 s.For the vertical ground motion, it is necessary to pay more attention to the difference between offshore and onshore ground motions with spectral period below 0.5 s.
谭景阳1,2，胡进军1,2，周旭彤1,2，杨泽西1,2. 海底与陆地地震动反应谱比定量分析[J]. 振动与冲击, 2021, 40(2): 213-219.
TAN Jingyang1, 2， HU Jinjun1, 2， ZHOU Xutong1,2， YANG Zexi1,2. Quantitative analysis on the difference of spectral ratios between offshore and onshore ground motions. JOURNAL OF VIBRATION AND SHOCK, 2021, 40(2): 213-219.
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