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By B. M. P. Pingua & Md. Nabiullah

About 60 to 70 percent of bulk explosives are used in Indian coalmines to achieve coal production for power generation. Coal India Limited (CIL) is the major coal producing company in India. The average production of CIL is 400 to 450 million tonne coal per annum. The major subsidiaries of CIL are Northern Coalfields Ltd., Mahanadi Coalfields Ltd., Bharat Coking Coal Ltd., Eastern Coalfields Ltd, South Eastern Coalfields Ltd. and Western Coalfields Ltd. Most of the mines of CIL have watery holes. Therefore, high water resistance bulk explosives are preferred for better out puts.

Jan 1, 2008

By MacDonald B. Johnson, Douglass P. Bacon

With the advance of science, rise of public interest in environmental matters, and continuing erosion of air quality, Federal and state regulators are demanding an increasing complex array of data concerning emissions produced by burning and detonating energetic materials. The U.S. Department of Defense, one of the world's largest consumers of energetic materials, now must characterize combustion products resulting from open burning/open detonation disposal operations. The catch-all phrase "below detection limits" no longer satisfies the regulators who now want testing to delve into the ppt level for volatile organic compounds and ppt level for semivolatile organic compounds.

Jan 1, 1995

By Omer Yilmaz Erkoc, Gulsec Uyar Aldas

Blasting techniques, which have been used for a long time in Turkey, are powerful and economical tool in producing raw material in mining, quarrying, construction .etc. industries. The development of the society within the world has resulted in a substantial increase in the scale of such industrial projects. However, the expansion of such activity has been matched by an increased public awareness of environmental issues, particularly when it occurs in relatively close proximity to residential areas. One of the most troublesome issues facing the mining, quarrying and construction industries when carrying out their blasting activities is that of ground vibration. Because, blasting induced ground vibration can reach to very far distances from the source and has the potential for damage to concern to the inhabitants of property.

Jan 1, 2002

By Rolf Koenig

After the Dynatronic firing system was demonstrated for the first time at the SEE conference in Miami in 1987, it was officially approved in Germany at the beginning of 1993. Dynatronic has now been on the market for 5 years. At present, it is used in several European countries and successful test series have been running in Australia.

Jan 1, 1998

By D P. Onag, B Mohanty

AECL Research (AECL) has constructed an Underground Research Laboratory (URL) as a facility for research and development in the Canadian Nuclear Fuel Waste Management Program. The objectives of the program are to develop and evaluate the technology to ensure safe, permanent disposal of Canada's nuclear fuel waste. Several multidisciplinary experiments and engineering demonstrations are planned for the URL over the next ten years.

Jan 1, 1991

By Mark D. Kirkbride

This paper outlines the process for designing a hard rock blast in an underground coal mine. The coal mine is located in Western Kentucky and operates four continuous miner units at 7 unit-shifts per day. The mine operates in the Western Kentucky No. 11 Seam with local variations from 4.5 - 5.5 feet seam thickness. The seam has sporadic siderite deposits. Usually these deposits do not significantly interfere with the mining process. When previous siderite deposits were encountered they were small enough to drop an entry for a couple of crosscuts. The blasting plan was called for after a siderite deposit was encountered in the belt entry at about one third of the panel length. The other sides of the panel had been previously mined and sealed so the decision was made to mine through the siderite deposit with the continuous miner instead of abandoning the panel. The deposit was approximately 300 feet in length down the belt entry. Mining through the deposit with the continuous miner was expensive in both terms of production and of wear and tear on the continuous miner. A blasting plan for the siderite deposits was designed to minimize damage to the continuous miner should a similar situation occur.

Jan 1, 1999

By Claude Cunningham

AEL has been developing electronic detonators continuously since 1986. It launched its first system for opencast mining in 1993, and now has two distinct product lines. The path has not been without great difficulty, but the determination to persevere was always buoyed by the strong encouragement of customers who experienced the transformed blasting results, as well as a clear vision of the enormous intrinsic value of the concept. The path of growth to dominant global supplier is traced through the separate application channels of coal stripping, quarrying, massive mining, opencast mining and narrow reef mining, to the first allelectronic detonator demolition blast in June 2001. Reasons for the slow coming to market of this highly desirable concept, which often coincide with reasons for the demise of various other systems, include the difficulty of safely mating electronics and explosives in a low cost environment; the extreme difficulties of achieving proper connection under mining conditions; the rapid rate of evolution of the technology, and the safety concerns raised by various accidents and incidents along the way. ED.s are now established as the way forward and are set to displace other systems in all serious applications. There is place for both programmable and pre-set delay systems.

Jan 1, 2002

By D D. Garg, D A. Wasson

Open pit blasting in India uses two types of explosives. First there are bulk explosives for wet and dry holes, and there are packaged explosives. The Indian open pit coal mining is projected to use 190 thousand metric tons of explosives in 1995. This volume is projected to grow for the next ten years, whereas the underground coal mining will hold fairly constant.

Jan 1, 1995

By Shad M. Sargand, Manseok Chang, Glenn A. Hazen

Customarily, peak particle velocity of surface wave vibrations has been the recommended criterion for the prediction of blast damage to structures. Currently blast spectrum and natural frequencies of a structure have been also recognized as important for predicting damage potential. While others have considered the importance of structural frequencies, they have not analyzed the structural response spectrum when establishing damage criteria.

Jan 1, 1992

By Jack Elorenta

A recent forum of mine operators revealed a continuing strong interest in alternative methods of freeing rock. A Rand Corporation report lists a continuous mechanical machine that would replace drilling and blasting as a priority for mine operators. Meanwhile, mounting evidence documents a dramatic cost benefit in processing where increased blast energy is available. The reasons for this dichotomy may be due to a number of factors.

Jan 1, 2002

By Michael J. Burrell

Sands Hill Coal, located in Wellston, Ohio produces coal for steam generation and crushed limestone for the aggregate market in southeastern Ohio. This paper concerns the blasting and production of the limestone which lies between the #5 and #4 coal seams. The limestone bed averages 8 to 10 feet in thickness and is overlain with 17 to 20 feet of shale from the floor of the #5 seam.

Jan 1, 1990

By G Dean Barrett, Ed Jr Smith, Calvin J. Konya

The purpose of the project was two fold: 1. To determine whether Pyrodex, a propellant, manufactured by the Hodgdon Powder Company, could be used as a substitute for high explosives for presplitting in granite and other materials. 2. To determine if Pyrodex, a slow reacting propellant which produces no stress waves in rock because it reacts subsonically, could cause the rock to crack similar to the results achieved with high explosives.

Jan 1, 1986

By Brian W. Stump

The cessation of testing of any nuclear explosive devices in all environments is the goal of the Comprehensive Test Ban Treaty. In order to assure compliance with such a treaty, an international monitoring system has been proposed. This system will include seismic, infrasound, hydroacoustic and radionucleide monitors located throughout the world. The goal of this system is the detection of any nuclear test. In preparation for this treaty, a series of monitoring system tests, focusing primarily on seismic observations, have been undertaken. The most recent of these tests, Group of Scientific Experts Technical Test Three (GSETT-3), provides valuable data for assessing future monitoring systems. During the course of this experiment, seismic events associated with earthquakes, nuclear explosions and mining explosions have been recorded. This presentation will discuss the numbers and types of mining explosions triggering the system, in a particular area. Possible implications for the mining industry will be explored.

Jan 1, 1997

By Karl Ingmarsson

A model for drilling productivity and total drilling cost is presented. It specifically addresses down-thehole drilling, but also covers other drilling methods. The important factors are: 1, productivity in tons drilled; and 2, total cost per drill ton. For non-blasthole applications these factors are measured in drill feet and cost per foot. The model focuses on the entire system and allows the operator to optimize the system based on individual drilling conditions.

Jan 1, 1998

By Charles A. Nork

Licensing of surface blasters as a regulatory requirement has been in effect in Pennsylvania for more than twenty years. Training of license applicants was begun in 1971 on a random basis. Formalization of training of applicants for surface blaster licenses was begun in 1980. Training is conducted on a regularly scheduled basis in specific locations throughout Pennsylvania. Training is conducted by Charles A. Nork with the assistance of one of five Department explosives field inspectors.

Jan 1, 1985

By Richard N. Snyder

In this system for connecting blasting caps to the initiation source, the need for a redundant design structure provides more reliable method of explosive initiation. This is accomplished by using a complete system starting at the blasting control, through the initiation line structure through the initiation line and connecting blocks to the blasting cap. The connecting structure between the initiation device and the blasting caps may be connecting blocks or other means.

Jan 1, 1995

By Malcolm Mellor

Practical procedures that have been developed for pre-split blasting and smooth blasting in common rocks are reviewed systematically. Topics covered include shothole spacing, charge weight per unit length of shothole, decoupling ratio, adjustments for explosive type and rock type, and weight of explosive per unit face area. Relevant properties of frozen rocks, frozen soils, and ice are compared with those of common unfrozen rocks, and appropriate adjustment of blast design is discussed. Interim relationships for the design of controlled perimeter blasting in frozen soils and massive ice are put forward, recognizing that additional experimentation is required. Special problems in controlled blasting of ice are discussed. These include effects of wet holes, delayed removal of burden, and submerged burden. Special attention is given to the cutting of ice islands and icebergs. An Appendix describes an operation in which the face of an ice wharf at McMurdo Sound was trimmed by pre-split blasting.

Jan 1, 1976

By Thomas E. Ricketts

An important part of underground mine planning and operations involves the reclamation of working areas after blasting before the mining cycle can continue. This is especially true for mining that must use large blasting operations in the vicinity of extensive underground workings. In an effort to develop a rational procedure for estimating mine damage produced by blasting, underground rock fall has been assessed for a large-scale blasting operation in oil shale. The amount of mine damage has been quantified in terms of manshifts of effort required to reclaim underground working areas after blasting. This has been further broken down into the three main phases of reclamation, i.e., scaling and excavation, rockbolting, and miscellaneous repairs on ventilation, utilities, etc. Different types of openings have also been assessed including level tunnels, incline drifts and rooms. The effect of repeated blasting on mine damage has also been documented with initial blasts producing more damage than subsequent blasts.

Jan 1, 1988

By D O. Doehring, W A. Charlie, W A. Lewis

The detonation of explosive charges releases large quantities of energy that can produce rock and soil deformations far from the detonation point Extensive data are available on blasting in general and on the performance of certain structures subjected to blast vibrations. However, only limited information is available on the performance of earthfill dams and other hydraulic structures subjected to blasting. The limited data indicate that, whatever the cause, one or several cycles of repeated strains in earthfill dams may cause residual porewater pressure increases. Limiting the peak particle velocity to less than 2.5 cm/s for operating dams constructed of or having foundations consisting of saturated, loose sands or silts and to less than 5 cm/s for other earthfill dams, should keep strains below the threshold strains required for residual porewater pressure increases to occur. Porewater pressures should be monitored throughout a blasting operation, and they should be allowed to dissipate, if necessary, before subsequent charges are detonated.

Jan 1, 1987

By Bradley C. Paul

Similar rock formations exhibit great variability in resistance to fragmentation during crater blasting. This observation was made during an attempt to calibrate the Kuz-Ram blast fragmentation model for crater blast geometries used in a modified in situ mining method for copper. The KuzRam equation is used to predict the fragment size distribution from blasting and includes a term called the "rock factor" to account for the fragmentation characteristics of the material. A data base of field scale crater shots in oil shale was available to supplement more limited data on copper ores. First, the blast geometry terms of the Kuz-Ram formula were modified to fit field data with various crater blast geometries. Rock factors were chosen to center the predicted curve on the curve representing observed fragmentation. Next, five possible sources of variability in rock factor were investigated: the grade of the oil shale, the aspect ratio of the charge, the type of explosive, the charge depth, and the rock itself.

Jan 1, 1989