SPECTRAL CHARACTERISTICS OF DYNAMIC RESPONSE OF SLOPE WITH DIFFERENT ANGLES OF INCLINATION
WANG Wenpei1,2,3,YIN Yueping2,LI Bin3,FENG Zhen3,YAN Jinkai2
(1. School of Water Resources and Environment,China University of Geosciences,Beijing 100083,China;2. China Institute of Geological Environment Monitoring,Beijing 100081,China;3. Institute of Geomechanics,Chinese Academy of Geological Sciences,Beijing 100081,China)
Abstract:Morphological characteristics of slopes determine the predominant frequency,which may amplify the incident seismic wave of the same or similar frequency range,thereby increase the slope dynamic response,and even trigger landslides. The microtremors and seismic observations were carried out in the adits along the Shiziliang slope surface in the meizoseismal area of Wenchuan earthquake(Ms 8.0). The spectral ratios of horizontal to vertical component from the microtremor and the seismic records of 3 aftershocks were analyzed and the spectral characteristic curves were obtained. It was found that the minimum predominant frequency occurred at the slope crest. The PGA amplification decreased initially and then increased with the elevation,exhibiting a concave shape. The biggest PGA amplification reached 1.25 at the slope crest. The phenomenon of the low predominant frequency corresponding to the high PGA amplification at the top of slope may be related to the ratio of slope height to the wavelength of incident wave. The ratio was 0.2 when the PGA amplification reached the maximum value. To further investigate the morphological amplification effect on spectral characteristics,dynamic analysis was performed using the finite difference software FLAC by inputting the waves of multiple frequencies from the seismic acceleration records at Wolong station during Wenchuan earthquake(Ms 8.0). 3 different angles of inclination were assumed for the slope being simulated. The calculated predominant frequencies of the slopes with different angles of inclination were found to be the same,which were verified by the results from inputting Ricker wavelets of different mono-frequencies. This indicated that the slope angle had no effect on the predominant frequency.
王文沛1,2,3,殷跃平2,李 滨3,冯 振3,闫金凯2. 不同坡角斜坡动力响应频谱特征研究[J]. 岩石力学与工程学报, 2015, 34(01): 121-128.
WANG Wenpei1,2,3,YIN Yueping2,LI Bin3,FENG Zhen3,YAN Jinkai2. SPECTRAL CHARACTERISTICS OF DYNAMIC RESPONSE OF SLOPE WITH DIFFERENT ANGLES OF INCLINATION. , 2015, 34(01): 121-128.
殷跃平. 汶川八级地震滑坡触发特征分析[J]. 工程地质学报,2009,17(1):29-38.(YIN Yueping. Features of landsldies triggered by the Ms 8.0 Wenchuan earthquake[J]. Journal of Engineering Geology,2009,17(1):29-38.(in Chinese))
[2]
殷跃平,王 猛,李 滨,等. 汶川地震大光包滑坡动力响应特征研究[J]. 岩石力学与工程学报,2012,31(10):1 969-1 982.(YIN Yueping,WANG Men,LI Bin,et al. Dynamic response characteristics of Daguangbao landslide triggered by Wenchuan earthquake[J]. Chinese Journal of Rock Mechanics and Engineering,2012,31(10):1 969-1 982.(in Chinese))
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