摘要
基于我国高速铁路沿线路排列的原位地震监测网络所必需的单台站预警模式,研究提出基于位移平方积分的地震震级预测方法,并与具有代表性的基于平均周期和基于位移幅值的地震震级预测方法进行比较。应用2008年汶川Ms8.0级地震的记录数据,分别推导基于位移平方积分、平均周期和位移幅值这3个特征参数的地震震级预测公式;对比3个公式的预测结果可知,基于位移平方积分的地震震级预测方法预测的震级偏差的标准差最小。通过对地震数据进行频域特性解析,拟合分析3s初始P波谱强度的对数与预测震级偏差之间的相关性,进而提出对震级偏差进行有效修正的方法,修正后的预测方法能够缓解预测大地震时出现的震级"饱和"现象,提高震级的预测精度。提出的基于位移平方积分的地震震级预测公式与修正方法可以实时、准确、快速、有效地预测复杂震源的地震震级,能够满足高速铁路单台站地震预警的严格要求。
Based on the mode of the earthquake early warning （EEW） for high speed railway using single station required by the in-situ seismic network along railway line in China, the earthquake magnitude prediction method from the integral of the squared displacement was presented and compared with the methods of period parameter and displacement parameter. Using the records of the Ms8.0 Wenchuan earthquake in 2008, the earthquake magnitude prediction formulas were derived respectively based on 3 characteristic parameters, namely, the integral of the squared displacement, average period and displace- ment amplitude. The prediction results were compared and it was known that, the standard deviation of the predicted magnitude difference of the method based on the integral of the squared displacement was the smallest. By analyzing the ground motion characteristics in the frequency domain, the correlations between the spectral intensity logarithm of 3 s initial P wave and prediction difference were studied, and then a method was proposed to revise the magnitude prediction difference. The revised prediction method could alleviate the phenomenon of ＂saturation＂ in predicting large earthquake magnitude; in addition, the predication accuracy was improved. The proposed magnitude prediction formula based on the integral of the squared displacement as well as the revision method can real-time predict the magnitude of impending earthquakes of complicated focal mechanisms with accuracy, speediness, effectiveness, which can meet the strict requirements of the EEW for high speed railway by single station.
出处
《中国铁道科学》
EI
CAS
CSCD
北大核心
2017年第2期127-132,共6页
China Railway Science
基金
国家自然科学基金资助项目(51278045)
国家自然科学基金高铁联合基金重点资助项目(U1434210)
铁道部科技研究开发计划项目(2010G08-C-1)
深圳地铁集团科研项目(SZ-CGM-KY001/2014)
关键词
高速铁路
地震预警
震级预测
单台站预警
位移平方积分
平均周期
位移幅值
High speed railway
Earthquake early warning
Magnitude prediction
Single station early warning
Integral of squared displacement
Average period
Displacement amplitude
