Effect of initiation location on distribution and utilization of explosion energy during rock blasting
- 221 Downloads
In mining, the explosive filled in each borehole is usually initiated by the detonator. However, the effect of the location of the detonator (i.e. initiation location), which determines the propagation direction of the detonation wave, cannot be ignored. In this study, the influence mechanism of initiation location was analyzed with the help of numerical simulation. Two blasting experiments were also conducted to study the effect of initiation location. The results indicate that the initiation location plays an important role in the distribution of the explosion energy transmitted to the surrounding rock mass. For the vertical borehole blasting, the peak particle velocity below the borehole can be reduced by 21.0–59.0% under bottom initiation, when compared to top initiation. The blast-induced damage of the remaining rock mass below the borehole is also weaker by 5.0–8.9% under bottom initiation. However, the problem of under break might become serious if the detonator is moved downwards in foundation excavation. The explosion energy is preferentially transmitted to the same orientation of the detonation wave during rock blasting. The bottom initiation, recommended by most previous researchers, is not always the best choice. The location of the detonator should be changed according to the onsite situations.
KeywordsInitiation location Explosion energy Distribution Utilization Rock blasting
This work is supported by National Natural Science Fund Project of China (51779190) and Hubei Province Technical Innovation Program (2017ACA102). The authors wish to express their thanks to all supporters.
- Blair DP (2010) Seismic radiation from an explosive column. Geophysics 75(1). https://doi.org/10.1190/1.3294860
- Gong M, Li JH (2002) A research on stress field of column and strip-shaped charge in different detonated points. J Univ Sci Technol Beijing 3(005). (In Chinese). https://doi.org/10.3321/j.issn:1001-053X.2002.03.005
- Hu H, Lu W, Yan P et al (2017) A new horizontal rock dam foundation blasting technique with a shock-reflection device arranged at the bottom of vertical borehole. Eur J Environ Civ Eng. https://doi.org/10.1080/19648189.2017.1399168
- Liu L, Chen M, Lu WB et al (2015) Effect of the location of the detonation initiation point for bench blasting. Shock Vib (6-7):1-11. https://doi.org/10.1155/2015/907310
- Plewman RP, Starfield AM (1965) The effects of finite velocities of detonation and propagation on the strain pulses induced in rock by linear charges. JS Afr Inst Min Metall 66:77–96Google Scholar
- Shen XM, Niu XQ, Lu WB et al (2016) Rock mass utilization for the foundation surfaces of high arch dams in medium or high geo-stress regions: a review. Bull Eng Geol Environ 1-19. https://doi.org/10.1007/s10064-016-0892-4
- The Professional Standards Compilation Group of Peoples Republic of China (SL47-94) (1995) Technical specification for construction of rock foundation excavation of hydraulic structures. Water Resources and Electric Power Press. (In Chinese), Beijing. https://doi.org/10.13751/j.cnki.kjyqy.2013.03.117 Google Scholar
- White JE (1963) Shear waves from explosive sources. Geophysics 28(6). https://doi.org/10.1190/1.1439296
- Xiao SY, Su LJ, Jiang YJ et al (2017) Numerical analysis of hard rock blasting unloading effects in high in situ stress fields. Bull Eng Geol Environ 1–9. https://doi.org/10.1007/s10064-017-1067-7
- Xu N, Wu J, Dai F, Fan Y et al (2017) Comprehensive evaluation of the stability of the left-bank slope at the baihetan hydropower station in Southwest China. Bull Eng Geol Environ 1–22. https://doi.org/10.1007/s10064-017-1018-3
- Zhang BP, Zhang QM, Huang FL (2001) Detonation physics. Weapon Industry Press, Beijing (In Chinese)Google Scholar