The use of air decks in production blasting in an open pit coal mine

被引：4
作者：
Jhanwar J.C. [1 ]
Jethwa J.L. [1 ]
机构：
[1] Ctr. Mining Res. Inst. Regional Ctr., 54-B Shankar Nagar
来源：
Geotechnical and Geological Engineering | 2000年 / 18卷 / 04期
关键词：
Air deck; Conventional; Economics; Fragmentation; Ground vibration; Open pit;
D O I：
10.1023/A:1016634231801
中图分类号：
学科分类号：
摘要：
The influence of air deck blasting on blast performance and blast economics and its feasibility has been studied in the production blasting of soft and medium strength sandstone overburden rocks in an open pit coal mine in India. The air deck blasting technique was very effective in soft and medium strength rocks. Its main effects resulted in reducing fines, in producing more uniform fragmentation and in improving blast economics. The fines were reduced by 60-70% in homogeneous sandstones. Oversize boulders were reduced by 80% and shovel loading efficiency was improved by 20-40% in blocky sandstones. The explosive cost was reduced by 10-35% dependent on the type of rock mass. Throw, backbreak and ground vibration were reduced by 10-35%, 50-80% and 30-94% respectively. For a particular rock mass and blast design environment, air deck length (ADL) significantly influenced the fragmentation. ADL as represented by air deck factor (ADF) in the range of 0.10-0.35 times the original charge length (OCL) produced optimum results. ADF beyond 0.35 resulted in poor fragmentation and in inadequate burden movement.
引用
收藏
页码：269 / 287
页数：18
相关论文
共 12 条
  • [1] Bieniawski, Z.T., Engineering classification of jointed rock masses (1973) Transactions of South African Institute of Civil Engineers, 15 (12), pp. 335-344
  • [2] Bussey, J., Borg, D.G., Presplitting with the new air deck technique (1988) Proceeding of the 14th Conference on Explosives and Blasting Techniquepp. Society of Explosives Engineers Annual Meeting, pp. 197-217. , Jan. 31-Feb. 5, Anaheim, California
  • [3] Chiappetta, R.F., Memmele, M.E., Analytical high-speed photography to evaluate air-decks, stemming retention and gas confinement in presplitting, reclamation and gross motion studies (1987) Proceeding of the Second International Symposium on Rock Fragmentation By Blasting, pp. 257-301. , Society for Experimental Mechanics, Bethel, CT, USA
  • [4] Fourney, W.L., Barker, D.B., Holloway, D.C., Model studies of explosive well stimulation techniques (1981) International Journal of Rock Mechanics and Mining Sciences and Geomechanics Abstracts, 18, pp. 113-127
  • [5] Jhanwar, J.C., (1998) Investigations Into Air Deck Blasting and Its Influence on the Blast Performance and Blast Economics in Open Pit Mines, p. 142. , M.E. Thesis, Nagpur University, Nagpur, India
  • [6] Knox, (1893) German Patent Specification, No. 67,793,1893
  • [7] Liu, L., Katsabanis, P.D., Numerical Modelling of the effects of air decking/decoupling in production and controlled blasting (1996) Proceedings of the Fifth International Symposium on Rock Fragmentation By Blasting, pp. 319-330. , Montreal, Canada, Mohanty, B. Balkema, A.A. (eds), Rotterdam
  • [8] Mead, D.J., Moxon, N.T., Danell, R.E., Richardson, S.B., The use of air-decks in production blasting (1993) Proceedings of the Fourth International Symposium on Rock Fragmentation By Blasting, pp. 437-443. , Vienna, Austria, July 5-8, Rossmanith, H.P. ad Ballkema, A.A. (eds), Rotterdam
  • [9] Melnikov, N.V., Marchenko, L.N., Effective methods of application of explosive energy in mining and construction (1971) Twelfth Symposium on Dynamic Rock Mechanics, pp. 350-378. , AIME, New York
  • [10] Melnikov, N.V., Marchenko, L.N., Seinov, N.P., Zharikov, I.F., A method of enhanced rock blasting by blasting, IPKON AN SSR, Moscow (1979) Journal of Mining Science, 6, pp. 32-42. , (Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Polyznykh Isko-Paemykh) Nov.-Dec
12