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By Keith Pucalik

One of the more important duties of the vibration consultant is to evaluate allegations of blasting damage by neighboring property owners. Unfortunately, the consultant is generally faced with having never seen the project, or preparing for litigation three or more years after blasting was completed. Under these circumstances, he must rely totally on blaster's logs and other contemporaneous records to conduct a meaningful evaluation.

Jan 1, 1990

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 Jack Eloranta

Proper selection of stemming has a profound effect on blast performance. This paper describes several methods of evaluating stemming performance in 16-inch blastholes. Tests are done on stemming ranging in size from nominal 1/4" crushed rock up to railroad ballast size rock (2 1/2" > diameter < 3/4"). Concrete plugs (both pre-cast and poured) are evaluated as well as air decking.

Jan 1, 1994

By M Dale White

Captive insurance companies have recently been discovered by risk management experts as a risk transfer vehicle and are very much in vogue. Actually, captive insurance companies are not a new phenomenon. Centuries ago, the first insurance organizations were what we today refer to as group or association captives. Early traders banded together to share the risks of ocean shipments writing ocean cargo coverage, the oldest form of insurance.

Jan 1, 1980

By Zoltan Susanszky

This paper discusses problems encountered when blasting under rivers for pipeline crossings. Many pipelines have recently been laid under the Danube River. Great care had to be taken to determine limits of detonation impulses from blasting operations in order that no damage would occur to structures at the water's edge, boats, and swimmers. Equations were derived from the results of this study which enable prediction of impulse levels.

Jan 1, 1977

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 J P. F Warkentin, A W. Bauer

Recently, significant improvements have been made in both blast design methods and blasting accessories. The introduction of extremely accurate blast delays now allows proper implementation of advanced blast designs. Thus the onus for future blasting improvements has moved from blast design to the need for ensuring that explosives quality is of the highest order. One measurement commonly used to assess explosive performance is the velocity of detonation (VOD).

Jan 1, 1991

By Stafan Rose, Art Madsen

Four years ago, Peabody’s North Antelope Rochelle Mine (NARM) site started experimenting withANFO and Liners in its Cast Blasting operations. The motivation to use ANFO was based on the following:1. ANFO generates more gas thereby resulting in greater heave/movement. 2. ANFO is a more consistent product because there are less components/ingredients. 3. ANFO when protected from water contamination does not produce NOx smoke.

Jan 1, 2007

By Scott Giltner, Allan Koski

Blasting is one of the lowest cost yet most critical parts of the mining cycle. This paper discusses the findings of an audit conducted on the blasting operation at an iron ore mine. The purpose of the audit was to review current blasting practices in order to identify opportunities for production/cost improvements. The approach taken in the audit was to observe general blasting practices, their related downstream effects and to compare current procedures to established best practices.

Jan 1, 2009

By Deane Boddorff

A 440 Volt AC power line is a typical power source for energizing electric blasting cap circuits in driving hard rock tunnels. A common misconception exists that the caps actually see 440 Volts. This paper describes an analysis of the entire blasting circuit determining the current flowing and the voltage drops through each component. If, from such an analysis, one determines that the current to the caps is too low or too high, the components that require changing are easily recognized.

Jan 1, 1975

By Hans Florin

This paper describes the modification of a nonelectric detonator which is ignited by a signal tubing. The heart of the new detonator lies in a so-called ignition transmitting element. The construction of the transmitting element is such that the detonator remains closed even after the signal tube has functioned. Due to the sealing of the delay element, this nonelectric detonator achieves the same accurate delay timing as high tech delay electric detonators and will not fail due to a sudden pressure loss.

Jan 1, 1988

By Leslie Taylor, W. Fourney, Uli Leiste

This paper presents the results from a series of tests conducted to investigate the total vertical impulse delivered to a target plate by a buried explosive charge. The tests were conducted at a very small scale but previous work has shown that small scale testing can predict impulse applied to plates in full scale. Non-deforming plates were used to determine the change in impulse delivered to targets as a result of changes in standoff distance and burial depth changes.

Jan 1, 2009

By Calvin Konya, Janos Foldesi

A bridge over a main line railroad system was scheduled for demolition. The bridge was made of reinforced concrete and spanned three mainline railroad tracks which could not be shut down due to blasting or demolition. To further complicate matters, the mainline tracks had high tension power lines running above the tracks, but below the bridge. These high tension wires provided the electricity for electrically powered trains. The tracks could not be damaged or disrupted, nor could the power line be broken.

Jan 1, 1992

By Lawrence Cheng-Kwang Hu

"Since the only available delay detonator in Taiwan is electric delay detonator, which can beaccidentally initiated by fire, i impact force, friction, static electric, lighting, radiotransmitter, and stray current etc., that always represent fatal threatens to the blasting crew.Fire, impact, friction can be Prevented by handling carefully; lighting also can be detectedwith proper instruments. But when a blaster find an unknown extraneous current in his welllaid down blasting cable; what a horror scence will be expected especially the electricdetonators have been connected already."

Jan 1, 1993

By Duane A. Houkom

Explosive demolition of concrete has been accepted as a safe and economical means of concrete removal for many years. I imagine that the early concrete blasters were experienced rock blasters who applied their knowledge to just another formation. Since a concrete foundation is generally located in a congested area, the owner is willing to accept the higher costs of mechanical removal,rather than promote "a new idea" to his management. This attitude is rapidly changing,making it possible to use the advantages of explosives in more congested locations.

Jan 1, 1982

By Mark S. Stagg, Stephen A. Rholl

The U.S. Bureau of Mines has developed computer software which uses fast Fourier transform (FFT) techniques to evaluate blasting data. The software is useful because it allows blasters to evaluate 1) the frequency content of ground vibration time history data; 2) the effects of initiator scatter on the frequency spectra of ground vibrations; and 3) the fragmentation distribution of rock muckpiles from photographs. A one-dimensional version of the software was used in the first two cases. Monte Carlo techniques were used to simulate the scatter of initiators.

Jan 1, 1995

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 Agus Setiabudi

East Pit Wira II Project in South Kalimantan, Indonesia with a radius of <500 meters (1,640 ft) from residential has about 454,168 tonnes of coal reserves, with a total remaining reserves of 3,369,383 tonnes (topography per end of June 2011). Thus, reserves may be lost as much as 13.48%. Therefore, it is needed to determine safe blasting technique which meets the Indonesian National Standards (SNI) No. 7571:2012 of vibration threshold, the maximum vibration of 3 mm/s (0.118 in/s) and air blast of 120 dB.

Jan 1, 2014

By Peter F. Bayer, Fred C. Drury

This paper deals with explosives regulations in the State of Wisconsin. As has been typical elsewhere, there has been considerable pressure to add additional restrictions over blasting in Wisconsin. What we believe to be a novel approach to the problem has been developed and is being implemented. Members of this Society have been instrumental in this approach whereby the emphasis of the regulations is directed at permissible levels of blasting resultants rather than at specific methods of blasting. It is our intent that this paper serve as a guide to others who may become involved in similar regulatory review in other states.

Jan 1, 1984

By Tom Medak, Don H. Cranney, G Paul McKay, R Douglas Reid

Explosive initiated afterblast dust explosions can occur in high sulfide ore mines when the flame generated by the detonating explosives ignites the sulfide dust produced from the blast, from previous blasting, or from other mining activities. The dust explosion can be a devastating, self-propagating fireball that will damage or consume any flammable object in its path. Damage to ventilation tubing is a frequent occurrence. These explosions also produce large quantities of sulfur dioxide and other noxious gases that can take several hours to clear from the mine. Thus, these occurrences can result in substantial losses in productivity to the mine.

Jan 1, 1994