摘要
在我国地震预警和烈度速报系统中,烈度计被广泛使用。烈度计的频谱特征主要是通过检定实验室进行标定,但在破坏性地震中,烈度计响应特点缺少必要的研究分析。该文以2022年四川泸定M_(S)6.8级地震为例,对比分析了烈度计记录和强震仪记录在噪声水平、信噪比(signal-to-noise ratio,SNR)、高通滤波截止频率(f_(HP))取值以及有效周期范围(T_(max))方面的特点,综合评价了烈度计记录的频谱特征,分析了噪声影响。得到以下结论:在整个频域范围内,烈度计记录的SNR要比强震仪记录平均意义上低一个数量级,可以估计烈度计动态范围较强震仪大致低20 dB;烈度计记录的最佳f_(HP)取值相较于强震仪记录存在更大的不确定性,尤其是在竖直方向上;烈度计记录的最佳f_(HP)取值更大,反应谱T_(max)较传统强震仪记录在水平方向小1~2 s,在竖直方向小3 s左右。该研究结果有助于合理应用烈度计记录,服务地震学和地震工程学相关研究。
In China’s earthquake early warning and intensity rapid reporting system,intensity meters are widely utilized.The spectral characteristics of intensity meters are primarily calibrated in testing laboratories.However,in destructive earthquakes,there is lack of necessary research and analysis on the response characteristics of intensity meters.The 2022 Luding,Sichuan M_(S)6.8 earthquake was taken as a case study,the comparison between MEMS records and strong-motion records were conducted in terms of the noise level,signal-to-noise ratio(SNR),optimal value of high-pass filter cutoff frequency(f_(HP))and effective period range(T_(max)).The noise effect of MEMS records was evaluated finally.The following conclusions are drawn:(1)Covering the entire frequency domain,the SNR of the MEMS records is lower by an order of magnitude on average than that of the strong-motion records,indicating that the dynamic range of the MEMS sensor is approximately 20 dB lower than that of the conventional accelerometer.(2)The optimal value of f_(HP)for the MEMS records has larger variability than that for the strong-motion records,standing out especially in the vertical component.(3)The optimal value of f_(HP)for MEMS records is larger,resulting in a smaller T_(max)in response spectra than that for the traditional strong-motion records,which is about 1-2 seconds shorter in the horizontal component and about 3 seconds shorter in the vertical component.The results will contribute to the rational application of MEMS records,serving correlated research in seismology and earthquake engineering.
作者
郭文轩
任叶飞
姚鑫鑫
岸田忠大
江鹏
王宏伟
温瑞智
GUO Wenxuan;REN Yefei;YAO Xinxin;KISHIDA Tadahiro;JIANG Peng;WANG Hongwei;WEN Ruizhi(Key Laboratory of Earthquake Disaster Mitigation,Ministry of Emergency,China Earthquake Administration,Key Laboratory of Earthquake Engineering and Engineering Vibration,Institute of Engineering Mechanics,Harbin 150080,China;Department of Civil Infrastructure and Environmental Engineering,Khalifa University,Abu Dhabi 127788,UAE;Department of Civil and Environmental Engineering,University of California,Los Angeles 90095,USA;Sichuan Earthquake Agency,Chengdu 610041,China)
出处
《振动与冲击》
EI
CSCD
北大核心
2024年第18期313-320,共8页
Journal of Vibration and Shock
基金
国家重点研发计划项目(2019YFE0115700)
国家自然科学基金项目(U2239252,51878632)
黑龙江省自然科学基金杰出青年项目(JQ2023E002)。
