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By S. P. Singh, Turgut Yalcin

The physical characteristics of blasted rock are fundamental variables affecting the economics of mining operations and are in fact the basis for evaluating the quality of a blast. A study was designed with the objective of quantifying the effect of muck size distribution on scooping operations in a mine.

Jan 1, 2002

By Ryan Redyke, Jared Redyke

The demolition of an old power plant boiler house in Parsons, Kansas calls for the use of some linear shaped charges. The steel is thick and the structure is heavy but gravity can be a blaster’s best friend. This entry did not win in a very competitive category. We thought it was worthy of coverage in the Journal of Explosives Engineering.

Jan 1, 2015

By Fred C. Drury

The Explosives Engineer's concern for personnel training in the safe, efficient and effective use of explosives materials has grown in recent years. Available training options have also grown. Today's options include off-site training seminars and in-house training departments, both of which represent significant cost to the smaller producer.

Jan 1, 1981

By Terry Graf, Bill Thompson, John Guenther

SYNCRUDE CANADA LTD.. operates the largest synthetic crude oil production facility in the world. Over 60,000,000 Bank Cubic Metres of oil sand is mined each year from their open pit located in Fort McMurray, Alberta. Despite the extremely cold temperatures encountered during the winter months and the problems associated with frost buildup, SYNCRUDE has continued to operate on a 12 month per year basis. In 1989 SYNCRUDE mine management embarked on a comprehensive Frost Blasting program to improve mine production of their oil sand moving equipment. The following paper will discuss the development of their frost blasting program to its current status.

Jan 1, 1993

By Steve Dillingham

In recent years, there has been a trend toward increasingly demanding blasting standards being enacted by local and regional regulatory authorities. The objective of this paper is to alert blasters of the difficulties that are created for blasting projects as a result of these restrictions, as well as the steps that can be taken to minimize future conflicts.

Jan 1, 1995

By Qingshou Chen, Paul N. Worsey

It has been recently argued that rock strength has little effect on the final results of pre-split blasting and is of only minor importance when blasting rock in general. However, it can be shown that the maximum borehole separation for optimal perimeter blasting results with constant borehole and loading configuration is strongly dependent on the tensile strength of the rock.

Jan 1, 1986

By J Edmund Hay, T S. Bajpayee

The Bureau of Mines is developing a test to determine the initiating strength of commercial detonators. Various tests of "detonator strength" are in use, but many of them do not correlate well with each other, and so far, there is little evidence that any of them correlates well with the ability of detonators to initiate detonation in an explosive. Therefore, the Bureau decided to attempt a measurement of the ability of detonators to initiate detonation. To this end, an explosive mixture of adjustable sensitivity was developed. This mixture was nitromethane sensitized with ethylene diamine, the sensitivity being "fine-tuned" by the addition of nitropropane.

Jan 1, 1992

By R C. Sittig

The manufacture of commerical detonating cord by the "wet process" technique is discussed. Raw material variability as a potential source of production problems is examined. Comparison to the "dry process" method is made. Inert samples, illustrating the cord's construction at various points in the production process, were distributed.

Jan 1, 1976

By C H. Dowding, P W. Linehan

Many of the technical and non-technical or human problems associated with blasting can be minimized through a proper preconstruction test-blast program.

Jan 1, 1986

By John F. Vynne

This paper will discuss the application of available monitoring technology on blasthole drills with the goal being to reduce costs and increase productivity. Case studies from the monitoring of blasthole drills in North American open pit mines will be used to illustrate the ability to meet these objectives.

Jan 1, 1997

By Michael D. Duffy, Martin W. Chenoweth

"Tenn Luttrell Company (TLC) is a major lime and limestone producer in the eastTennessee area. The property, which isreferred to as the Chesney Mine, has been mined from the surface and underground overthe past 20 years. The ore body consists of three major zones of chemical grade limestonewhich lay at a dip of 30 _ 65 degrees. In July of 1989, Tenn Luttrell Company made thedecision to reopen the underground operations which had been suspended during a time ofincreased surface mining."

Jan 1, 1993

The use of angled shot holes can be extremely effective in blasting faces that either have a great deal of toe burden or where it is difficult to give a drill access to a face due to backbreak and face erosion. However many quarry operators are wary of using angled holes because of the perceived possibility of increased flyrock and uncertainty of the driller's abilities to drill at the designed angle.

Jan 1, 1994

By Peter Bellairs

It is generally expected that drilling and blasting be a routine part of a mining process where the blastholes are drilled, left for a period of time and then primed, loaded with explosive, stemmed and then detonated via an appropriate surface initiation system. The occurrence of a premature detonation(s) therefore results in a great deal of consternation and disruption to the mining operation.

Jan 1, 1997

By William C. Pearson

In past years, the usual justification for underground mining of limestone has been the depth of the overburden, perhaps 100 feet thick or more. At our Okolona Quarry in suburban Louisville, Kentucky, the overburden is usually shallow -- it averages 8 to 10 feet in thickness. However, in July 1980, we began development of an underground limestone mine on that property which also includes surface mining operations.

Jan 1, 1983

By R M. Bhatawdekar, A I. Theresraj, H S. Venkatesh

Wadi Limestone Quarry is one of the largest captive mines of Associated Cement Companies Ltd, India. The mine management wanted to extend the excavation as close to the plant as possible for maximum exploitation of the deposit. The National Institute of Rock Mechanics and the management of Wadi Limestone Quarry carried out comprehensive investigations to evolve a methodology to control vibration and flyrock within safe limits.

Jan 1, 1999

By Alfred Osborne

Progressive cavity type pumps are widely used by commercial explosive manufacturers for pumping water gel, emulsion and emulsion / ANFO blend explosives. Tests by explosives companies and investigations into incidents have shown that this type of pump can develop dangerously high temperatures when operated deadheaded or dry. [i.e. with no flow of product through the pump.] In some tests and incidents, explosion or detonation of the explosive (or residual explosive) in the pump has resulted.

Jan 1, 2002

By John L. Floyd

One of the key factors that controls the overall profitability of surface operations is the required volume of excavated material. If the overall angle of final walls can be maximized the amount of material excavated will be reduced. However, as the slope angle becomes steeper the wall's factor of safety decreases. As a result, the development and implementation of efficient wall control blast designs becomes critical to achieving stable walls. Many site specific conditions should be taken into account when defining the methods that will be used to lessen blast induced wall damage. This paper will discuss the steps needed to properly evaluate the site and develop efficient designs. Four variations of wall control blast designs will be evaluated in terms of cost and performance. In addition, the paper will include the quality controls needed to successfully implement and refine the blast design.

Jan 1, 1998

By David R. Ziegler

Blasting complaints are as unpredictable as human nature. Being prepared to speak to the complainant, and having a good idea of what you should say, or what NOT to say, may affect the evolution, and eventual resolution of the complaint. The person taking that first phone call will probably not be responsible for resolving the complaint. However, the person in charge should respond to the complainant ASAP, the same day, if possible.

Jan 1, 1998

By J R. Phin

The properties of all available modern blasting initiation techniques are reviewed. Primadets are nonelectric initiators, the nonelectric features of the system eliminates concern of premature initiation from static or stray currents. The loading techniques are simple and a minimum of training is required. There is no limitation in the number of necessary sequences in which the Primadet need be connected for initiation. This flexibility improves vibration control,and often reduces costs due to increased fragmentation.

Jan 1, 1975

By Shulin Nie

The dead-pressing phenomenon in emulsion explosives is wellknown. Research work on this subject has been carried out at the Swedish Detonic Research Foundation for the last few years. Several experiments with emulsion explosives under dynamic pressure condition have been carried out both in iron pipes and in blast holes in rock. The main object was to study the critical amplitude and duration of the pressure causing the explosive to be dead-pressed.

Jan 1, 1993