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This paper discusses development, test data, field trials, performance, application and possible economics of high-energy blasting agents fueled with Nitropropane that can be bulk loaded into downholes or packed into waterproof packages at densities between 1.10 and 1.25 gm/cc and that yield calculated detonation pressures of 50 kilobars in small diameters to 100 kilobars in diameters over six inches. Using high-density nitrate, downhole densities of over 1.4 have been attained in field trials with correspondingly high calculated detonation pressures.

Jan 1, 1977

By Jack Eloranta

This paper documents the relationship between material handling and processing costs compared to blasting cost. The old adage, "The cheapest crushing is done in the pit", appears accurate in this case study. Comparison of the accumulated cost of: powder, selected wear materials and electricity; indicate a strong, inverse correlation with powder factor (lbs powder/long ton of rock). In this case, the increased powder cost is more than offset by electrical savings alone.

Jan 1, 1995

By Dale S. Preece, J Paul Tidman, Stephen H. Chung

A discrete element computer program named DMC_BLAST (Distinct Motion Code) has been under development since 1987 for modeling rock blasting (Preece & Taylor, 1989). This program employs explicit time integration and uses spherical or cylindrical elements that are represented as circles in 2-D. DMC_BLAST calculations compare favorably with data from actual bench blasts (Preece et al, 1993).

Jan 1, 1997

By Raymond V. Adolphson

The introduction of a new explosive component in 1955-56, called ANFO, featured much safer, effective blasting characteristics when compared to dynamite, accompanied by a notable reduction in cost. These savings mounted as borehole diameter or depth was increased with ANFO volume subsequently enlarged.

Jan 1, 1983

By Edward J. Walter

An ancillary effect to every blasting operation is the generation of vibration Extensive research has been performed for the purpose of understanding, controlling, and predicting this vibration An examination of these studies clearly shows a variability in the resulting vibration effects It seems logical to expect that identical blasting procedures should produce identical vibration levels, but this is rarely the case. There is a distinct pattern of variation.

Jan 1, 1980

By Dennis A. Clark, Richard E. Calvin

As the scarcity of mineral resources increase and subsurface mining activities expand along with simultaneous surface mining in coal, industrial minerals and rocks, along with metals, the need to insure safe conditions is paramount.

Jan 1, 1981

By Pat McLaughlin, J R. (Dick) Daniels

Current practice in establishing quarries in remote areas with hilly or mountainous terrain tends to the use of airtracs (or similar pioneering units) drilling horizontal holes to establish a face, followed by bench development with light excavating equipment. The authors propose the use of a hybrid coyote blast design that incorporates long-round tunneling techniques. This method would, in effect, use down-the-hole (DTH) drills to advance the drift cut to the final depth, allowing longer and more rapid drift advances, and replace the cross-cut drifts with clusters of DTH holes to achieve the same explosives distribution.

Jan 1, 1995

By Ian A. Niell, Alastair C. Torrance

A joint research programme conducted by BHP Central Research Laboratories and Du Pont Wesfarmers Pty Ltd examined the effect of the size of cast primers on the run up and steady state detonation velocities of ammonium nitrate based explosives as a function of blasthole diameter. Both continuous and point to point velocity of detonation measurement techniques were used. The field trials examined a number of the Du Pont HDP series of primers in conjunction with ANFO, emulsion and watergel explosives. Results indicate that the run up velocity of 187mm diameter ANFO charges is negligible using cast primers as small as 1509. However, emulsion and watergel explosives did exhibit run up in both 187 and 311mm diameter blastholes, independent of the size of primer. This could last from 7 to 10 blasthole diameters.

Jan 1, 1990

By Shijie Qu, Paul N. Worsey

Pre-splitting has become widely adopted for the formation and protection of final surface rock excavation profiles in both large scale civil construction and highway rock cuts. Jointing has been shown to affect the success of pre-splitting and the smoothness of the resulting profile, however, only closed joints have been investigated. Frequently jointing that is closed at depth is open at and near the surface due to weathering, reduced stresses and ground water percolation. In many instances, problems are associated with surface rock layers whereas at depth these problems are either reduced or do not exist.

Jan 1, 1987

By Jeffrey N. Deisher, H Y. Fang, Richard P. Scheller, Robert M. Koerner

The need to adequately quantify cracking in structures in the vicinity of blasting activity becomes more important each year. This urgency comes about through a growing number of complaints and lawsuits between the various parties involved, i.e., operator/owner, government, and complaintant. It is felt that existing rules and regulations (mainly based on peak particle velocity of the soil or rock adjacent to the structure in question) fall short of such quantification and lead to confusion in adequately assessing structural damage.

Jan 1, 1977

By Benedict C. Di Duca

In the underground construction industry. when bidding work, not only is the contractor faced with determining if rock: is in existence within the parameters of his work. he must also estimate the quantity and the most efficient method of removal.

Jan 1, 1990

By Everett Clausen, Richard Walker

CIL/EVANinc and the Canadian Explosives Research Laboratory of the Government of Canada have evolved a concept developed by Research Energy of Ohio, into a landmine neutralization system that is the most innovative to date.

Jan 1, 1999

By Donald Jonson

The Arlanda Link project is for the time being the most interesting project in Sweden, concerning rock and blasting technology. The total amount of rock excavated beneath Arlanda airport comprises 800 000 m³ divided in four parallel tunnels measuring a total length of 8,5 km, with a rock covering of only 5-15 m between the tunnel roof and existing terminal buildings.

Jan 1, 1997

By William Everett, Jack Eloranta

United Taconite is an iron ore mine operated by Cleveland-Cliffs Inc (Cliffs) located near Eveleth, Minnesota. The mine, originally known as Eveleth Taconite Mines, was purchased in December 2003 by Cliffs (70%) and Laiwu Steel (30%). The mine site, known as the Thunderbird Mine, produces taconite ore for delivery by rail to the company’s Fairlane plant, located approximately 10 miles to the south near Forbes, Minnesota. At the plant, the crude ore is ground, concentrated and processed into pellets for steel industry customers. Total pellet production capacity is about 5.4 million long tons (Ltons) per year.

Jan 1, 2006

By Thomas J. Snyder

Modern quarry management should be alert to every opportunity to improve productivity and reduce operating costs. In this paper, the author outlines areas in which explosives suppliers should be encouraged to propose changes. He also supplies guidelines for evaluating these proposals, suggests yardsticks for measurement, and stresses the need to be open-minded when dealing with imaginative, innovative concepts.

Jan 1, 1988

By R Malo, A Yetter

The use of large diameter blastholes for underground mining began approximately twelve years ago and are now routinely employed in a variety of ore types and stope designs. These large boreholes, ranging in size from 4 1/2 inch to 8 inch diameter, were first utilized in the same fashion as in open pit bench drilling. However, a variety of changes quickly followed in order to accommodate the unique conditions encountered while using a blasthole sloping method.

Jan 1, 1984

By J R. "Dick" Daniel

One of the more common tasks in blast management is the adjustment of: shot geometry, explosive energy, and shot timing parameters to achieve changes in blast outcomes and costs. Many of these shot parameters, once a delayed blast is initiated, are modified by the development of new free faces which change the original or static input values to dynamic values. These newly generated dynamic values are easily calculated and find use in fine tuning shot adjustments and in rationalizing blast outcomes in a systematic manner.

Jan 1, 1996

By S S. Kahlon

India is a large and growth market for explosives and accessories, which has dramatically changed from complete import dependence to self sufficiency, and now has an exportable surplus. The largest single user is coal mining which is continuing to show a healthy growth with opencast mining becoming increasingly dominant. The explosives industry has kept pace with mining and today all the well renowned explosives technologies of the world are available in the country. While slurry explosives are popular in large diameter, NG based explosives continue to be preferrred in small diameter usage. Emulsion explosives have had a good market response. ANFO usage is limited due to local reasons. As the mine size is increasing, the demand for bulk-on-site explosives is growing. Prices of explosives and accessories are cheap compared to international levels. The user industry is mainly Government owned mines whose profitability is not satisfactory. Explosives industry is over licensed in terms of manufacturing capacity, which is likely to put pressure on the viability of some of the explosives manufacturing units. Scope exists for optimization of blasting parameters through the use of computerized blasting models. The explosives industry is faced with new challenges and opportunities.

Jan 1, 1987

By Quentin L. Rhoton

"The use of explosives in a surgical manner was approved to facilitate, due to time constraints, anextremely significant paleontological find in the Plunket Point area of the Dominion Range, Antarctica. The organic material revealed by surgical blasting techniques may have altered basic scientific dogma on Antarctic glaciation theory."

Jan 1, 1999

By Ron Woolf, Corry Goumans

This paper describes rock slope remediation performed along America’s first Superhighway, the Pennsylvania Turnpike and in particular, the specialized drilling equipment designed and built by Pacific Blasting to complete this work. This S-month project was performed on an existing rock cut slope within the Bedford Narrows, a gap formed by the Juniata River through Evitts Mountain. These rocks are in the folded Juniata and Tuscarora Formations within the Valley and Ridge Province and strike northeast with near vertical to slightly overturned bedding.

Jan 1, 2001