Open AccessStudy on blasting vibration characteristics of metro tunnel based on wavelet packet technology
Author(s) -
Shibin Jiang,
Chen Zhao,
Shang Gao,
Xinyu Ji,
Xianpeng Lv,
Hao Sun,
Jihui Chen
Publication year - 2021
Publication title -
iop conference series. earth and environmental science
Language(s) - English
Resource type - Journals
eISSN - 1755-1307
pISSN - 1755-1315
DOI - 10.1088/1755-1315/638/1/012075
Subject(s) - vibration , wavelet , range (aeronautics) , network packet , transmission (telecommunications) , signal (programming language) , structural engineering , energy (signal processing) , rock blasting , engineering , computer science , acoustics , telecommunications , geotechnical engineering , aerospace engineering , physics , artificial intelligence , computer network , quantum mechanics , programming language
Wavelet packet technology has been widely applied in the study on blasting vibration transmission law of overlapping tunnels. The previous research focused on vibration transmission law of the distant area---a range more than 20m, but for the close area---a range less than 10m, research seldom has been carried out. Therefore, this paper, based on a overlapping tunnel project in Qingdao, reveals the blasting vibration transmission law of the close field as well as how the numbers of free surfaces affect the law. Firstly, at the site,the blasting vibration data both in front and rear of the working faces including the cutting area (a free face) and the spreading area (two free faces) in a newly-built tunnel are obtained; Secondly, the wavelet packet technology is applied to analyze the data of blasting vibration frequency and energy distribution characteristics. Finally, it is concluded that different free facing with different numbers can lead to different main frequency distribution range and different law of main frequency band changing with distance when blasting vibration transmit within the close field; and the vibration signal energy in front and rear of the working face in cutting area and spreading area is differently distributed in the directions of 3 channels. Combining blasting vibration signal frequence with energy factors, this paper puts forward the constructive suggestions on the safety protection of existing tunnels and provides reference for studying the law of blasting vibration transmission of overlapping tunnels. CLC classification number: 0389 TD235 Document identification code: A