频率下降率法对2011年新西兰6.3级地震液化的盲测
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摘要
场地液化实时监测是减轻地震灾害的新手段,其核心是建立依据强震记录识别场地液化技术,但目前建立的方法尚不成熟,可靠性也缺少实际地震的检验。2011年新西兰地震中液化及其震害现象显著,为检测现有液化识别方法提供了条件。利用该次强震记录,采用孙锐和袁晓铭以往提出的频率下降率法对记录场地液化进行了盲测,为今后方法改进提供思路。针对震中距小于50 km的全部27条原始强震记录进行了识别,有9个场地识别为液化场地,其余为非液化场地;对两个已报道为液化的场地,频率下降率法给出了正确的识别结果;识别出的液化场地主要集中在克赖斯特彻奇市东侧Avon河两岸,这一结果与报导定性相符;发现有两个场地原始强震记录存在疑点,经处理后给出了修正结果。
The real-time liquefaction monitoring and warning techniques are novel ways to mitigate liquefaction hazard.The key point for the techniques is to establish a reverse liquefaction detection method based on seismic records.However,the reliability of the existing liquefaction detection methods is lack of verification by earthquake records.There were serious liquefaction damages in Christchurch in New Zealand Earthquake in 2011 and creates a wonderful chance to exam the existing liquefaction detection methods.The acceleration records in the earthquake are employed to perform the blind detection of liquefaction situation by frequency decrease rate(FDR) method presented by the authors before.The results indicate that in all 27 sites of which the distances from epicenter are less than 50 km;there are 9 liquefaction sites and others are identified as non-liquefaction sites.Two liquefaction sites among the 9 liquefaction sites;have been confirmed by the news reports;and it means the detection results by FDR method are correct.The identified liquefaction sites by method are mainly located near the Avon River in the eastern of Christchurch,which are agreeable to the corresponding news reports.From the analysis of the paper,two earthquake records are in doubt because of the un-normal phenomena with significant high frequency components in the middle or beginning part of the waves,separately;and the revised results for the two seismic waves are given after filtering the records.
The real-time liquefaction monitoring and warning techniques are novel ways to mitigate liquefaction hazard.The key point for the techniques is to establish a reverse liquefaction detection method based on seismic records.However,the reliability of the existing liquefaction detection methods is lack of verification by earthquake records.There were serious liquefaction damages in Christchurch in New Zealand Earthquake in 2011 and creates a wonderful chance to exam the existing liquefaction detection methods.The acceleration records in the earthquake are employed to perform the blind detection of liquefaction situation by frequency decrease rate(FDR) method presented by the authors before.The results indicate that in all 27 sites of which the distances from epicenter are less than 50 km;there are 9 liquefaction sites and others are identified as non-liquefaction sites.Two liquefaction sites among the 9 liquefaction sites;have been confirmed by the news reports;and it means the detection results by FDR method are correct.The identified liquefaction sites by method are mainly located near the Avon River in the eastern of Christchurch,which are agreeable to the corresponding news reports.From the analysis of the paper,two earthquake records are in doubt because of the un-normal phenomena with significant high frequency components in the middle or beginning part of the waves,separately;and the revised results for the two seismic waves are given after filtering the records.
引文
[1]孙锐,袁晓铭.基于强震记录快速识别场地液化的频率下降率法[J].岩土工程学报,2007,29(9):1372-1379.SUN Rui,YUAN Xiao-ming.The method of frequencydecrease rate for fast identification of site liquefactionfrom surface acceleration records[J].Chinese Journal ofGeotechnical Engineering,2007,29(9):1372-1379.
[2]KOSTADINOV M V,YAMAZAKI F.Detection of soilliquefaction from strong motion records[J].EarthquakeEngineering and Structural Dynamics,2001,30:173-193.
[3]SHIMIZU Y,WATANABE A,KOGANEMARU K,et al.Super high-density real time disaster mitigationsystem[C]//Proceedings of 12th World Conference ofEarthquake Engineering.Auckland.New Zealand:Silverstream,2000.
[4]SUZUKI T,SHIMIZU Y,NAKAYAMA W.Characteristics of strong motion records at the liquefiedsites and judgment for liquefaction[C]//Proceedings of11th European Conference on Earthquake Engineering.Paris:Balkema A A,1998.
[5]YUAN X M,SUN R,CHEN L W,et al.A method fordetecting site liquefaction by seismic records[J].International Journal of Soil Dynamics andEarthquake Engineering,2010,30(4):270-279.
[6]孙锐,唐福辉,陈龙伟,等.现有液化识别方法对比分析[J].岩土力学,2011,32(增刊1):20-26.SUN Rui,TANG Fu-hui,CHEN Long-wei,et al.Comparative analysis of existing liquefaction detectionmethods[J].Rock and Soil Mechanics,2011,32(Supp.1):20-26.
[7]李英民,董银峰,夏洪流,等.考虑频率非平稳特性的地震波ARMA模型住址方法[J].重庆建筑大学学报,2000,22(增刊):124-138.LI Ying-min,DONG Yin-feng,XIA Hong-liu,et al.Amethod on synthesis spectrum-compatible accelerogramsusing ARMA models considering the non-stationaryfrequencies[J].Journal of Chongqing JianzhuUniversity,2000,22(Supp.):124-138.
[2]KOSTADINOV M V,YAMAZAKI F.Detection of soilliquefaction from strong motion records[J].EarthquakeEngineering and Structural Dynamics,2001,30:173-193.
[3]SHIMIZU Y,WATANABE A,KOGANEMARU K,et al.Super high-density real time disaster mitigationsystem[C]//Proceedings of 12th World Conference ofEarthquake Engineering.Auckland.New Zealand:Silverstream,2000.
[4]SUZUKI T,SHIMIZU Y,NAKAYAMA W.Characteristics of strong motion records at the liquefiedsites and judgment for liquefaction[C]//Proceedings of11th European Conference on Earthquake Engineering.Paris:Balkema A A,1998.
[5]YUAN X M,SUN R,CHEN L W,et al.A method fordetecting site liquefaction by seismic records[J].International Journal of Soil Dynamics andEarthquake Engineering,2010,30(4):270-279.
[6]孙锐,唐福辉,陈龙伟,等.现有液化识别方法对比分析[J].岩土力学,2011,32(增刊1):20-26.SUN Rui,TANG Fu-hui,CHEN Long-wei,et al.Comparative analysis of existing liquefaction detectionmethods[J].Rock and Soil Mechanics,2011,32(Supp.1):20-26.
[7]李英民,董银峰,夏洪流,等.考虑频率非平稳特性的地震波ARMA模型住址方法[J].重庆建筑大学学报,2000,22(增刊):124-138.LI Ying-min,DONG Yin-feng,XIA Hong-liu,et al.Amethod on synthesis spectrum-compatible accelerogramsusing ARMA models considering the non-stationaryfrequencies[J].Journal of Chongqing JianzhuUniversity,2000,22(Supp.):124-138.
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