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On the Law of Roadbed Slope Vibration Caused by Tunnel Blasting
(1 China Construction Shandong Investment Co., Ltd., Jinan 250101; 2 China Construction Port Group Co., Ltd., Qingdao 266000;3 School of Mechanics and Civil Engineering, China University of Mining and Technology, Beijing 100083; 4 China State Construction Engineering Corporation, Beijing 100037)
Abstract In order to study the law of slope vibration caused by fine delay control blasting, equivalent charge and
equivalent distance are introduced and a new formula of vibration velocity attenuation is established using dimensional analysis method by taking the fine delay control blasting at the entrance of Heiyu tunnel reconstruction and extension as the engineering background; based on the measured data of four times of test, fitting verification is conducted and a comparison with Sodev′s empirical formula is carried out. Wavelet packet analysis is adopted to study the distribution of vibration energy. The research shows that: the prediction error of traditional Sodev′s formula is as high as 27.39% regarding this project, and the measured vibration velocity is generally larger than the calculated one, which is not conducive to guiding construction, while the max. prediction error of the improved empirical formula is 18.41%, indicating that the improved formula has good applicability; the blasting vibration energy is mainly concentrated in the range of 0-109.375 Hz and it is mostly concentrated in the range of 0- 46.875 Hz, around 1% of
vibration energy is larger than 109.375 Hz; As the distance increases, the vibration energy concentrates the area of low frequencies, and the high-frequency energy is gradually absorbed by the rock mass.
Abstract:
In order to study the law of slope vibration caused by fine delay control blasting, equivalent charge and
equivalent distance are introduced and a new formula of vibration velocity attenuation is established using dimensional analysis method by taking the fine delay control blasting at the entrance of Heiyu tunnel reconstruction and extension as the engineering background; based on the measured data of four times of test, fitting verification is conducted and a comparison with Sodev′s empirical formula is carried out. Wavelet packet analysis is adopted to study the distribution of vibration energy. The research shows that: the prediction error of traditional Sodev′s formula is as high as 27.39% regarding this project, and the measured vibration velocity is generally larger than the calculated one, which is not conducive to guiding construction, while the max. prediction error of the improved empirical formula is 18.41%, indicating that the improved formula has good applicability; the blasting vibration energy is mainly concentrated in the range of 0-109.375 Hz and it is mostly concentrated in the range of 0- 46.875 Hz, around 1% of
vibration energy is larger than 109.375 Hz; As the distance increases, the vibration energy concentrates the area of low frequencies, and the high-frequency energy is gradually absorbed by the rock mass.
FAN Xiangxi1,
4 CAO Baoshan2 SHAN Renliang3 ZHANG Youbo2 WEI Haibing4 SONG Yongwei3 LIU Jian3
.On the Law of Roadbed Slope Vibration Caused by Tunnel Blasting[J] MODERN TUNNELLING TECHNOLOGY, 2020,V57(4): 127-135