Author:
Zhou Xianshun,Zhang Xuemin,Wang Lichuan,Feng Han,Cai Chenzhi,Zeng Xiaohui,Ou Xuefeng
Abstract
AbstractThe drilling and blasting method is widely used in tunnel engineering. The accompanying airblast may damage structures and annoy nearby occupants. The prediction of airblast overpressure (poa) outside the tunnel is necessary to improve the safety of blasting works. A study of propagation characteristics of airblasts induced by tunnel blasting was carried out through experimental and numerical studies. The results indicate that the distributions of the poa outside the tunnel were anisotropic, which does not conform to the decay law of an explosion in free-field. The propagation of airblasts induced by tunnel blasting is related to the airblast shape. The phenomenon that the poa along the axial direction of the tunnel was higher than along other directions can be explained by the numerical results of the process of airblasts. The airblasts outside the tunnel traveled as a spherical wave, but the pressure was not uniformly distributed. After an airblast plane wave with high speed and high pressure inside the tunnel was transmitted out of the tunnel, its inertia strengthened the pressure in the axial direction. The airblast outside the tunnel is related to the propagation distance Rout, the angle from the measurement to the tunnel axis α, and the pressure intensity p0 at the tunnel portal. Subsequently, an ellipsoidal contour curve of the poa outside the tunnel was plotted, and therefore a new prediction equation was validated by numerical results and field data. Finally, the newly proposed methodology guided the blast design.
Funder
the Hunan Postgraduate Research Innovation Project
Fundamental Research Funds for Central Universities of the Central South University
National Natural Science Foundation of China
Science and Technology R&D Project of China Railway 18th Bureau Group Co., Ltd
Publisher
Springer Science and Business Media LLC
Reference30 articles.
1. Jia, B., Zhou, L., Cui, J. & Chen, H. Attenuation model of tunnel blast vibration velocity based on the influence of free surface. Sci. Rep. 11(1), 1–13. https://doi.org/10.1038/s41598-021-00640-9 (2021).
2. He, Z. et al. A combination of expert-based system and advanced decision-tree algorithms to predict air-overpressure resulting from quarry blasting. Nat. Resour. Res. 30, 1889–1903. https://doi.org/10.1007/s11053-020-09773-6 (2021).
3. Faramarzi, F., Ebrahimi Farsangi, M. A. & Mansouri, H. Simultaneous investigation of blast induced ground vibration and airblast effects on safety level of structures and human in surface blasting. Int. J. Min. Sci. Technol. 24, 663–669 (2014).
4. Afeni, T. B. & Osasan, S. K. Assessment of noise and ground vibration induced during blasting operations in an open pit mine—a case study on Ewekoro limestone quarry, Nigeria. Min. Sci. Technol. 19, 420–424 (2009).
5. Norén-Cosgriff, K. M., Ramstad, N., Neby, A. & Madshus, C. Building damage due to vibration from rock blasting. Soil Dyn. Earthq. Eng. 138, 106331 (2020).