摘要
在岩溶地区为减少铁路隧道工程安全隐患,需对在建隧道隧底进行岩溶探测工作,查明岩溶发育情况并及时整治。地震映像法是快捷无损的高效探测手段。利用岩溶、岩体破碎等地质体对地震波的衰减吸收及对地震波频谱影响规律有别于完整围岩,采用Hilbert-Huang变换方法获得地震映像记录的瞬时频率在时间空间上的分布情况,探讨经验模态分解后各阶模态的频谱分布规律。对某铁路隧道实测数据在剔除坏道、能量均衡、滤波预处理后,采用HHT方法进行处理,分析岩溶和岩体破碎区瞬时频率分布特征。综合利用时域和频域特征识别岩溶发育及空间展布情况,提高隧底地震映像法数据解释精度和岩溶识别准确性。
In the karst district,in order to reduce the safety hazard of railway tunnel engineering,it is necessary to carry out karst detection at the bottom of the tunnel,find out the karst development situation and provide timely control.Seismic imaging method is a fast,nondestructive and efficient detection method.Based on the difference between the attenuation and absorption of seismic wave and the frequency spectrum of seismic wave caused by karst and broken rock mass,the temporal and spatial distribution of instantaneous frequency recorded by seismic image is obtained by Hilbert-Huang Transform method.The frequency spectrum distribution of each mode after empirical mode decomposition is discussed.The measured data of a railway tunnel were processed and analyzed by HHT method after bad track removal,energy equalization and filtering pretreatment.The instantaneous frequency distribution characteristics of karst and broken rock mass area were discussed in detail.The data interpretation accuracy and karst identification accuracy of the underground seismic imaging method are improved by using the characteristics of time domain and frequency domain to identify the karst development and spatial distribution.
作者
陈清
CHEN Qing(China Railway Fifth Survey and Design Institute Group Co.Ltd.,Beijing 102600,China)
出处
《铁道建筑技术》
2024年第10期14-18,共5页
Railway Construction Technology
基金
中铁第五勘察设计院集团有限公司科技研发计划项目(T5Y2022-C24)。
关键词
地震映像
时频分析
HHT
岩溶识别
seismic imaging
time-frequency analysis
Hilbert-Huang Transform(HHT)
identification of karst