GOSPODARKA SUROWCAMI MINERALNYMI Tom 24 2008 Zeszyt 4/3 R. MIKHELSON*, S. KHOMERIKI*, D. KHOMERIKI*, K. DZEBISASHVILI*, H. TUDESHKI**, S. ROSSBACH** The computer program of designing drilling and blasting operations in open-cast mine Introduction Designing a complex of drilling and blasting works on open cast mines is made by considering an economic expenditure of material and monetary resources, maintenance of set granulometric composition and the convenient form of disorder of the blown up mountain weight, qualitative study of a bench bottom with the minimal destruction of contour massif, and also a high level of safety of works. 1. Theory The structure of standard project about drilling and blasting works on open cast mines is presented in work of Bashkuev et al. 1983 in rather detailed manner. It includes the general data on object of works, data about a relief of a surface, a geological structure of a massif and its hydro-geological features; the accepted or existing mine technical conditions of manufacture of explosive works; calculation of charges, parameters of their arrangement and the recommendation at the choice of schemes of detonation; Calculation of radiuses of dangerous zones on scattering pieces, seismic effect of explosion and action of shock air waves in conformity in instructions “Uniform safety rules at explosive works” (Vasichuk 1993). ** L.P.P.L. G. Tsulukidze Mining Institute, Tbilisi, Georgia. ** Technical University of Clausthal, Germany. 164 To the project is applied: The situational plan of open cast mines in scale 1:10,000 or 1:2000 with drawing radiuses of dangerous zones on action of explosion; typical cuts of the blown up block; the scheme of charge arrangement on a bench; a charge design in a borehole; the scheme of an explosive network. The computer program of designing drilling and blasting works on open cast mines is developed with the purpose of calculation of boreholes of charges of loosening and elements of their arrangement in the blown up block, including such parameters, as resistance on a bench bottom, the sizes of a cell of a grid of boreholes, weight of a charge in a borehole, a design of a charge depending on its degree of watering, an interval of delay between explosions of numbers of boreholes. The program allows choosing the optimum scheme of detonation depending on a category of explosibility of rocks and requirements concerning decrease in seismic action of explosion. The settlement formulas most approved in a world practice are brought in the program (Bashkuev et al. 1983; Gushin 1972; Sukhanov & Kutuzov 1983; Rtubetski et al. 1994; Baron & Kantor 1989), allowing to receive values of required parameters of drilling and blasting works. Determination of optimal type of explosives is based mainly upon the multi-criteria assessment of efficacy of industrial explosives, including compositions containing con- version explosive compounds. Multi-criteria efficiency analysis of new explosive substances enables to compare their feasibility indications with that of standard explosive substances. Relative capacity of new explosive substances is determined from below expression: r ' e 'V' [1+ (r H DH DC P )] (1) K P ,H = r H e H VH [1+ (r ' D' DC P )] where: r ' and r H – density of standard and new explosive substances correspondingly [t/m3], e ' and e H – specific explosion energy of standard and new explosive substances correspondingly [kJ/kg], V' and VH – gas explosion volume of standard and new explosive substances correspondingly [l/kg], D' and DH – detonation speed of standard and new explosive substances correspondingly [km/sec], D – density of exploded rock formations [t/m3], CP – speed of longitudinal wave in massive [km/sec]. Relative power capacity of new explosive substance is estimated by index of: e vH DH (2) K m ,H = e v' D ' 165 where: e v' and e vH – energy volume concentration of standard and new explosive substances correspondingly [mJ/m3]. Comparative economy of application efficiency of new explosive substances is deter- mined from expression: é æe P q öù (3) K 'q ê1- ç m ' H + ' çe P ÷ú × 100% ÷ ë è mH ' K E øû where: e m ' and e mH – explosion energy of standard and new explosive substances correspondingly [kJ/kg], P' and PH – 1 kg costs of standard and new explosive substances correspondingly, q' – basic specific drilling rate by application of standard explosive substance [m/m3]. e vH (4) KE = e v' The set of initial data for estimation of economic efficiency of new explosive substances includes physical and mechanical parameters of rock formation massifs, mining and tech- nical conditions and costs indices. It is known, that the degree of reliability of results of calculation depends on comple- teness of a set of the entrance parameters describing physical-mechanical and technological properties of a massif of rocks. Considering this circumstance in the program of introduction an identification scale on which it is possible to estimate values of missing parameters, and the main thing to establish the most probable limits of change specific power consumption of explosive destruction of drilled block (kJ/m3) – the size defining the specific charge of applied or recommended explosive (kg/m3). Normative data are entered into the program under the specific charge of drilling, also at use of reference explosive (Avdeev et al. 1986) and settlement formulas for an opportunity of reduction of this parameter to any explosive. The program allows to choose optimum diameter of boreholes and to correct the specific charge of explosive, depending on blockiness of a massif of rocks and the set (maximal) size of a piece of crushed product. Positive feature of the program is the possibility of a choice of optimum types of explosive for the set mine technical conditions. It is especially important in conditions of saturation of the market wide assortment of the polytypic industrial explosives essentially differing on the structure, characteristics and technological properties. The choice of type of industrial explosive is carried out in view of hydro-geological conditions, presence in 166 a massif of the excited environments entering in exothermic realization with nitrate of ammonium (Strakhova et al. 2006), sensitivity to external influences and its cost. The mode of a choice of optimum type of explosive is based on comparison of technical and economic parameters of any explosives, including conversion and similar characteristics of reference explosive, the type of it is chosen by the user. 2. Results The program allows making all necessary calculations for projected and maintained open cast mines. Below is given the list of initial data entered into the program (Base Microsoft Visual Fox Pro): II. The information on mine technical conditions of open cast mines: — Density of rocks, — Strength of rocks at uniaxial compression, — Degree of watering of charges, — Degree of fissuring of a massif, — Annual production rate of open cast mine on mountain weight, — Capacity of excavator bucket (loader), — Diameter of a borehole (for operating open cast mines), — The maximal size of conditioned piece, — Type and actual specific power consumption of applied explosive on separate groups of rocks (for operating open cast mines), — Diameter of explosive boreholes (for operating open cast mines), — The actual specific charge of drilling (for operating open cast mines). II. The information on cost indexes: — Cost of 1t of the reference explosive used for a number of years on the given deposit (for operating open cast mines), — Cost of drilling of 1m borehole. The choice of means of programming provides: — Opportunity of updating an available database by entering data on the new explosives acting on the markets, — Ease of modifying program modules and screen forms, and also printed forms if they be required in the further. The program is constructed in a dialogue (interactive) mode and carries out the following primary goals: — Modernization of a database about explosives, — Choice of optimum type of explosive for the given mine technical conditions with an estimation of their relative working capacity, capacity and economic efficiency;, — Calculation of key parameters of drilling and blasting works, 167 — Calculation of intervals of delay and choice of optimum schemes of short delay detonations, — Calculation of radiuses of dangerous zones at explosion of borehole charges. At the decision of each of the specified problems should be considered the stage of open cast mine preparation (projected or maintained), type of explosive boreholes (dry, partially or completely watered), physical-mechanical properties of rocks and technical characteristics on a massif. Below is given the full list of problems and the subtasks which are carried out by the computer program: 1. Updating the databases about the explosives used in a mining industry and construction. — Updating the prices of explosives; — Updating a database by data on the new explosives acting on the markets. 2. Calculation of relative efficiency of explosives with the purpose of a choice of an optimum kind. — Calculation of efficiency of explosives and parameters of drilling and blasting works. – For operating open cast mines with watered boreholes, – For operating open cast mines with dry boreholes, – For projected open cast mines with watered boreholes, – For projected open cast mines with dry boreholes. — Comparison of efficiency of the chosen explosives, including conversion, with any explosive accepted by user as reference and calculation of key parameters of complete set of drilling and blasting works with observance of conditions of safety of work of boring rig on a ledge. – At homogeneous charges, – At combined charges. 3. Calculation of intervals of delay and a choice of schemes of short delay detonations. 4. Calculation of radiuses of dangerous zones at detonation of borehole charges. — At homogeneous charges. – Calculation of radius of a dangerous zone on scattering pieces of rocks, – Calculation of radius of a dangerous zone on seismic effect of explosion, – Calculation of radius of a dangerous zone on action of shock air wave, — For the combined charges (with the same subtasks, as for homogeneous). The major moment at the decision of problems is input of initial data. In this connection, at construction of the program, the interface has been simplified with the purpose of a conclusion of all helps on the screen for an opportunity of using the program almost without preliminary training. Considering, the circumstance that not all the initial data demanded for calculation of relative efficiency of explosives and parameters of drilling and blasting works, are in advance known, the program provides an opportunity at input initial given to display help data from which the user can choose value of the missing parameter corresponding concrete object. 168 It is also necessary to note other feature of the program: at definition of parameters of drilling and blasting works for the combined charges, calculations are spent for all spectrums of watered boreholes – from zero up to 100 %, owing to what the user can easily see change of technical and economic parameters depending on a degree of boreholes watering. Conclusion Proceeding from the aforesaid, it is obvious, that it is calculated on application by its engineers-experts in the field of explosive business. The offered program will essentially facilitate a choice of optimum explosive and calculation of parameters of drilling and blasting works will enable quickly to see competing variants. On the basis of the executed calculations the user can easily execute computer to the schedule for concrete objects. REFERENCES  A v d e e v F.A., B a r o n V.L., G u r o v N.V., K a n t o r V.Kh., 1986 – The normative directory about drilling and blasting works. 5th publishing house (ed), processing and supplemented: 511. Moscow, Nedra.  B a r o n V.L., K a n t o r V.Kh., 1989 – Technique and technology and blasting operations in USA: 376. Moscow, Nedra.  B a s h k u e v E.B., B e i s e b a e v A.M., B o g a t s k i V.F., 1983 – Designing explosive works in the industry. In second publishing house (ed), processing and supplemented: 359. Moscow, Nedra.  G u s h i n V.I., 1972 – The book of problems on explosive works: 160. Moscow, Nedra.  S t r a k h o v a A.G., P r e s n i a k o v N.D., T a r a s o v V.A., G a b d u l l i n R.Kh., 2006 – New industrial explosives for detonation of sulphide ores. Magazine of Mining 5, 41–42, Moscow, Publishing House “Ores and Metals”.  S u k h a n o v A.F., K u t u z o v B.N., 1983 – Destruction of rocks by explosion. The textbook for high schools, second publishing house (ed), processing and supplemented: 344. Moscow, Nedra.  T r u b e t s k i K.N., P o t a p o v M.G., V i n i t s k i K.E., M e l n i k o v N.N., 1994 – The open mining works: 540. Moscow, Bureau of Mines.  V a s i c h u k M.P., 1993 – Uniform safety rules at explosive works: 238. Accepted by Gosgortekhnadzor of Russia 1992. Moscow, Scientific production association OBT. 169 KOMPUTEROWY PROGRAM PROJEKTOWANIA WIERCEÑ I ROBÓT STRZELNICZYCH W KOPALNI ODKRYWKOWEJ S³owa kluczowe Materia³y wybuchowe, roboty strzelnicze, kopalnia odkrywkowa Streszczenie Program do projektowania wierceñ i robót strzelniczych w kopalniach odkrywkowych opracowano z myœl¹ o obliczaniu ³adunków do otworów i elementów ich rozplanowania w bloku, ³¹cznie z takimi parametrami jak opór na dnie wyrobiska, wielkoœci celi sieci otworów wiertniczych, waga ³adunku w otworze, projekt ³adunku zale¿ny od stopnia jego uwodnienia, opóŸnienia miêdzy eksplozjami otworów. THE COMPUTER PROGRAM OF DESIGNING DRILLING AND BLASTING OPERATIONS IN OPEN-CAST MINE Key words Explosives, blasting works, open cast mining Abstract The program of designing drilling and blasting works on open cast mines is developed with the purpose of calculation of boreholes of charges of loosening and elements of their arrangement in the blown up block, including such parameters, as resistance on a bench bottom, the sizes of a cell of a grid of boreholes, weight of a charge in a borehole, a design of a charge depending on its degree of watering, an interval of delay between explosions of numbers of boreholes.