Satpaev Kazakh National Technical University, Almaty, Kazakhstan:

P. V. Dolgov, Professor, Doctor of Engineering Sciences, dolgov_p@mail.ru
V. S. Shevtsova, Associate Professor, Candidate of Engineering Sciences

The article reports the results of the theoretical and experimental investigations aimed to evaluate a cracking zone radius as the key parameter of shooting aimed to prevent gas-dynamic events in potash mines. The formula to calculate the cracking zone radius after shooting in salt rocks is suggested. The authors give the calculated radii of cracking zones in salt rock, sylvinite and carnallite after shooting in holes of different diameter and length and with different amount of explosive. It is found that under shooting in outbursthazardous salt rocks with a single hole with a diameter of 70–80 mm charged with a granulated explosive, the mine personnel safety is ensured by a drivage with a cross section up to 12 m²; on the other hand, efficiency of shooting with the holes 42 mm in diameter is lower than with the holes 70–80 m in diameter by 2–3 times.

1. Rauche H. Die Kaliindustrie im 21 Jahrhundert. Erfurt, Springer Vieweg, 2015. 580 s.
2. Laptev B. V. Emergency Situations at Verkhnekamsky Potash-Magnesium Minefield. Bezopasnost truda v promyshlennosti. 2009. No. 8. pp. 28–31.
3. Andreyko S. S., Litvinovskaya N. A., Lyapina T. A. Control of gas-dynamic processes in floor rock mass in sylvinite bed AB of the Upper Kama Potassium Salt Deposit. Gornyi Zhurnal. 2015. No. 4. pp. 69–72. DOI: 10.17580/gzh.2015.04.16
4. Dolgov P. V., Polyanina G. D., Zemskov A. N. Methods of forecast and prevention of gas-dynamic phenomena in potassium mines. Alma-Ata : Nauka, 1987. 175 p.
5. Karasyuk N. F. Hazards of gas-dynamic phenomena in potassium mines. Rudnik budushchego. 2012. No. 2(10). pp. 54–58.
6. Dolgov P. V. Development of boron-potassium deposits, hazard according to the gas-dynamic phenomena. Mining in Kazakhstan. State and prospects : materials of international conference. Almaty, 2000. pp. 165–167.
7. Müller U. Über daz Auftreten von CO₂ im Merre. Kaligebert. Freib – A – 101. 1958.
8. Laptev B. V. Historiography of Accidents when Developing Salt Mines. Bezopasnost truda v promyshlennosti. 2011. No. 12. pp. 41–46.
9. Begur M. Überblick über den Bergbau in Deutschland. Glukauf. 2014. No. 3. S. 46–49.
10. Hedlund F. H. Past explosive outbursts of entrapped carbon dioxide in salt mines provide a new perspective on the hazards of carbon dioxide. Intelligent Systems and Decision Making for Risk Analysis and Crisis Response. The 4^th International Conference on Risk Analysis and Crisis Response (RACR2013). August 27–29, 2013, Istanbul, Turkey. pp. 763–769.
11. Hedlund F. H. The extreme carbon dioxide outburst at the Menzengraben potash mine 7 July 1953. Safety Science. 2012. Vol. 50, Iss. 3. pp. 537–553.
12. Andreyko S. S., Ivanov O. V., Nesterov E. A., Golovatyy I. I., Beresnev S. P. Research of salt rocks gas content of III potash layer in the Krasnoslobodsky mine field. Gornyi Zhurnal. 2013. No. 6. pp. 69–72.
13. Zemskov A. N. Gas-bearing capacity of potassium deposit mines. Rudnik budushchego. 2012. No. 2(10). pp. 44–53.