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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

Drilling through unconsolidated material I need to drill blastholes through a mix of consolidated and unconsolidated material. This material is hung up in an underground ore pass. The total length of the holes would be approximately 200 feet. We have attempted to drill through the material with conventional ITH drilling, but were unsuccessful. Does anyone have a suggestion? I am more than willing to bring in a contractor to do the job, if they have solid experience with this type of problem.

Jan 1, 2011

By Thomas E. Brown

With the ever increasing public sensitivity to our environment, the blasting industry can no longer be concerned with just drilling and blasting. Government regulations, augmented by public pressure, require that the industry must be more diligent in preventing spills, disposing of distressed products and packaging materials, controlling fumes and dust, preventing product contamination, developing environmental impact studies, and preventing unnecessary regulations. These liabilities in conjunction with those of vibration, air overpressure and flyrock will continue to greatly impact the industry.

Jan 1, 1995

By M J. Ball, R Watt

ICI has developed a new electrical shotfiring system which has markedly improved safety features and operational advantages over existing initiating systems. The development of the 'Magnadet' Electric Detonator and the related product 'Magna' Primer were described in a paper presented at the 1981 S.E.E. Annual Conference. Since then the system has been adopted in many different applications and conditions around the world. The present paper describes these applications, the experience gained and the more recent developments which have taken place.

Jan 1, 1982

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 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 Thomas M. Keevin, Gregory L. Hempen

Natural resource agencies, under various regulatory authorities, are challenged with permitting underwater explosive use while at the same time protecting aquatic resources. Deciding on whether or not to allow use of explosives requires striking a balance between development and aquatic resource protection. A company's goal in underwater explosive use is to select methods that are both expedient and cost effective. Use of explosives is often the best alternative for engineering reasons or economic considerations. Over and above legal requirements, indiscriminate destruction of fish and other aquatic resources is not in a company's best interests because of concerns relating to public image, as well as the need to secure future contracts.

Jan 1, 1995

By Dale S. Preece, Stephen H. Chung

"In bench blasting, the distribution of loaded explosives with respect to the burden rock has strong effects on digging especially at the toe area. Blast design often focuses on other results such as percent-cast or fragmentation, sometimes leaving a diggability problem at the toe of the blast that is not discovered until excavation. A method for assessing the influence of blast design on diggability has been developed. This method relates the kinetic energy and rock displacement experienced by the material in the muckpile to its diggability. Simulation of the blast along with the calculation of kinetic energy and diggability is done with the discrete element computer program DMC_BLAST(DMC: Distinct Motion Code)."

Jan 1, 1999

Hello, everyone. Way back in 1965, Devine and others at the US Bureau of Mines showed that a presplit fracture plane did not affect vibration levels transmitted across the plane (RI 6695).

Jan 1, 2010

By Douglas R. Burns

During the summer of 1989, Maine Drilling and Blasting of Gardiner, Maine was contracted by Cayer Corporation of Harvard, Massachusetts to drill and blast an interceptor trench at the Nyanza Chemical Superfund Site in Ashland, Massachusetts.

Jan 1, 1991

By Stephen A. Rholl

Computer software has been developed which uses fast Fourier Transform (FFT) techniques to analyze the frequency spectrum associated with peaks in ground vibration time histories. The procedure consists of filtering the FFT of a time history into individual frequency components.

Jan 1, 1996

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 Stanley L. Lippincott

A number of Federal and State agencies require formal training for blasters. Federal agencies often specify the need for initial training involving all job responsibilities as well as periodic refresher training to assure adherence to current operating procedures. failure to provide and document such training can result in substantial penalties.

Jan 1, 1995

By C Robert Scott

Yes - We have figures on Explosives Manufacturers ! But, on the 500 or 600 explosives contractors, unless you happen to specialize in shooting oil wells, we have no numbers. As you know, the Insurance Industry lives on numbers, the larger the better. They collect the amount of premiums and losses on each line of insurance they write.

Jan 1, 1980

By Larry Mirabelli, Gerard J. O'Brien

"The construction of the Third Harbor Tunnel is a key element of the Central Artery TunnelProject. The tunnel is to traverse Boston Harbor directly linking South Boston to EastBoston. The tunnel is a cut and cover tunnel as opposed to a bored tunnel. The cutdimensions are 95' wide, 110' deep and approximately 4000' in overall length."

Jan 1, 1993

By R. Wharton, M. Bagley

The paper reviews the likely introduction of a European directive covering the sale of pyrotechnic articles in member states of the European Union. The background and structure of the directive are described, together with the range of products covered (which includes fireworks, theatrical pyrotechnics, vehicle airbags and seat belt pretensioners, and certain cartridges). Possible timescales and the implications for industry are also discussed.

Jan 1, 2007

By Wm. Reisz

There is no universal standard for Standard Operating Procedures (SOP’s). Every blasting operation has its own unique circumstances, its own methodologies and its own unique demands. It would be nearly impossible to create a one-size-fits-all document that would be totally appropriate for every blasting scenario. But there are universal objectives that should be adopted in any set of blasting SOP’s.

Jan 1, 2010

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 ISEE

Micrometer Crack Response to Vibration and Weather, by Prof. Charles H. Dowding of Northwestern University, adds to Prof. Dowding’s already important contributions to the industry with his “Construction Vibrations” books. This new book reports and interprets important data on crack response that are essential for differentiating the unseen effect of weather on structural cracking from the usually much smaller effect of vibration. In addition, the book contains detailed descriptions of data collection methodology.

Jan 1, 2010