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By Ann Barron, Paul Downing

Those employed in the explosives industry must have a keen familiarity of the explosives products they handle, the safety pro c e d u res they must follow, and the increasing number of laws and regulations governing blasting operations in order to perform their duties satisfactorily. For this reason, companies must make certain that their employees have the necessary knowledge and full understanding of their blasting and non-blasting responsibilities. Consequently, training is one of the most important elements in any company’s safety program.

Jan 1, 2004

The following situation was submitted as an ethics case study for inclusion in the Journal. To the best of our knowledge, they are based on actual circumstances encountered in the field. Blowing the Whistle Protecting Confidentiality or Doing the Right Thing? This case centers around a construction job and involves a contractor, subcontractor/blaster, and a farmer/homeowner who lives near the job site. It is essentially a study of professional ethics versus morality, our professional code of conduct versus what is right or wrong.

Jan 1, 2007

By Larry: McAnuff Schneider, Edward Walter, Gordon Shaw, Daniel Grieco, Dennis Clark

During the 1998 Annual Conference of the International Society of Explosives Engineers (ISEE), the Seismograph Section established a subcommittee for the purpose of compiling a list of all regulations pertaining to limits imposed on ground vibration generated by blasting. The goal of this project was to determine the vibration regulatory levels being enforced, with the further intention of examining their scope, and uniformity. A secondary purpose was to evaluate the consistency of the existing regulations with the current scientific findings on structural response and damage potential.

Jan 1, 2001

By Shao Li, Chen Zhiming, Wu Jihong

In this paper,powder emulsion explosives,which have high sensitivity and strong detonation force,have been studied by applying emulsion technology to the production of the present powder ones.Under the condition of #8 industrial detonator initiation,the distance of air gap propagation is 110~180mm,brisance !3.5mm, lead block test value 325ml and detonation velocity 3000~4000m/s for small diameter (35mm) explosive cartridges.In addition to these,the factors effect on are investigated by experimental study and theoretical analysis.

Jan 1, 1991

By Douglas Anderson

In the early 1980s, a method for controlling blast vibrations other than by modifying the Scaled Distance came into use. Research studies had indicated that blast vibration could be simulated by detonating a signature hole with the vibration monitored at critical locations, and then using a computer to superpose the waveforms with varying delays. By choosing delay times that create destructive interference at frequencies that are favored by the local geology, the “ringing” vibration that excites structural elements in houses and annoys neighbors could be reduced.

Jan 1, 2008

By Feng Shuyu Yang Nianhua

According to the results of high speed photography tests, particle velocity measurement tests and the digital calculation with TP2 software, the shape of shock wave, the declined laws of the shock wave propagation speed and the peak particle velocity are described and analyzed in detail. New viewpoints about the theories of blasting fragmentation based on analysis of the progressive pictures of the fracture region are given. The formula for calculating the depth of fracture regions is established on the basis of the new viewpoints.

Jan 1, 1997

By Trevor Garbutt, Peter Bellairs, Jason Sander, Glenn Shaw

The Yarrie Iron Ore mine is located in the Pilbara region of Western Australia some 200km eastsoutheast of Port Hedland, the closest large regional centre. The mine is owned by BHPIO who has contracted a large Australian mining contractor Roche Bros to be responsible for the total mining, crushing and trainloading functions. This paper describes a drill and blast optimisation program, resulting from the introduction of a new emulsion matrix called Titan@ Red used to manufacture both HANFO and pumped emulsion ANFO blends.

Jan 1, 1999

By Carlos Agreda

A general review of the comminution theory and also the general differential equation of the comminution are described, analyzed and discussed in order to be applied to rock blasting. Some size distribution functions are reviewed and discussed to determine which of them represents better the cumulative low size distribution F(x) as a function of the nominal particle size (x), for the rock blasting fragmentation. Based on the mathematical comminution model before presented a formula to calculate the burden (B) is developed and discussed.

Jan 1, 1994

By Virgil J. Stachura, Larry R. Fletcher, Paul V. Sterk, Matthew N. Plis

The large diameter blastholes now being used in underground mining have caused concern because of their increased potential for damaging openings and creating rockfall hazards. In response to this situation, the Bureau of Mines is conducting research to reduce the amount of overbreak and damage to the perimeter of underground openings. This paper presents the results of tests with decoupled charges in 6.5 inch diameter blastholes, and unloaded guide holes, in Vertical Crater Retreat (VCR) stope panels at the Homestake underground gold mine in Lead, SD.

Jan 1, 1991

By D. Bartley, R. McClure, W. Reisz

Ever since the 8ms criterion was developed in the early 60’s there has been an ongoing debate among many blasters as to its actual value in controlling ground vibration. The perpetuation of the myth surrounding the 8ms window can be partly attributed to its simplicity and convenience as a means for regulatory compliance. Unfortunately, the mindset that many blasters have adopted has hindered the development and use of more effective techniques and in many cases can actually be counter productive to vibration control.

Jan 1, 2006

By Robert B. Hopler

The Hercudet™ non-electric delay blasting cap system has exhibited outstanding performance and economic results in surface work. The versatility inherent in the system, which allows the combining of the built-in cap delays with the tubing delay (i.e.: the travel time of the gas reaction through the tubing), has resulted in outstanding blast results. Examples of blast patterns used, details of the blast design process, and recently-developed methods of use of Hercudet for surface initiation of detonating cord downlines are given in the paper.

Jan 1, 1978

By Michael McDougall

"Suncor Inc. Oilsands Group, Mining Operation in Northern Alberta, Canada, has beenblasting to loosen the oilsands to increase production and decrease maintenance of the hugebucketwheel excavators for over twenty years. In 1991 an area of the mine wasencountered which had a working face in excess of 130 feet. In order to maintain theproduction objective, the blasting department took on the task of providing as much of ablasted face to work with as possible. In doing this Suncor has exceeded several knownrecords in production blasting."

Jan 1, 1993

By John W. Gunnett

The purpose of this afternoon’s presentation is to highlight the investigative proce dures employed to complete an engineering audit of a mining operation. Skelly and Loy has been retained to perform operational audits throughout the nation’s coal fields, The need for such studies is generally associated with long term coal supply contracts and is typically initiated by the utility company. However, a number of projects have been commissioned by mining companies while others have been jointly funded by the utility and mining company.

Jan 1, 1992

By Dale Ramsey

Emulsion explosives have become the product of choice for many blasting applications and are not limited to just extreme wet hole conditions or special application environments as in the past. Today’s novel emulsion technology has evolved over many decades, allowing a great diversity of formulations, Emulsion explosives can be effectively designed to produce very high energies, cap sensitive high explosive cartridges to bulk blasting agents, with varying viscosities, stable VOD’s, excellent water resistance, long shelf life and sleep time. They are also conducive to the mixture of emulsion, An/F0 blends in varying proportions and are amenable to any type of sensitizer. The key to a stable, reliable and consistent emulsion formulation is the careful mixing of the internal phase, which consists of a solution of oxidizer salts suspended as microscopically fine droplets, with the surrounding continuous fuel phase. There are few blasting applications today where some form of an emulsion explosive cannot fit the application. In massive, hard rock, dense, tightly jointed and fine grained rock types, the emulsion explosives are the best choices in creating new fracture networks for good fragmentation with a few alternatives. In such environments, emulsions with expanded drill patterns often result in better economics than the use of straight AnLFo. This paper will cover emulsion formulations, sensitizing options, product testing, material handling, and blast optimization, Emulsion explosives characteristics have also proven to reduce adverse environmental effects such as noxious fumes, ground vibration, and airblast while still remaining cost effective.

Jan 1, 2000

By P D. Katsabanis, W Roberts

Commercial explosives exhibit non ideal behaviour which is very difficult to model. The fume spectrum produced by commercial explosives apart from its practical significance for underground mining is of great theoretical importance since it reveals information about the chemistry of the detonation process. Emulsions, watergels and dynamites were tested under various degrees of confinement in an one cubic metre closed chamber. Sand, concrete, steel and copper pipes were used to alter confinement. The degree of confinement was found to significantly influence the quantity (litres/kg of explosive) and the relative proportions of toxic and non-toxic fumes (percent of total fume measured). These results lead to further confinement testing using various rock materials. Fume results, and thus detonation performance were found to be dependent on the type of rock material used for confinement. Materials such as dolomite, limestone, and granite were found to result in a relatively high detonation efficiency of the subject explosive as shown by the distribution of detonation fume products. Conversely materials such as sandstone, talc and massive sulphide resulted in fumes suggesting low relative detonation efficiency. Fumes appear to be a sensitive indicator of the completeness of reactions occurring within the expansion zone of the composite emulsion explosive, while the detonation velocity is relatively insensitive to small variations in confinement. Estimates of sonic velocities of the confining rock materials were found to show no correlation with VOD results. However good correlation between fume results and sonic velocity suggests that the performance of an explosive as indicated by the resulting fume spectrum is affected by the degree of confinement.

Jan 1, 1992

By Qian (Ken) Liu, Remi Proulx

A large scale blast damage project was carried out over the past two years at INCO Ltd Manitoba Division co-funded by the Canada/Manitoba Mineral Development Agreement. The experiment was conducted at the T-3 Mine in two mining stopes with an experimental drift developed in the hanging-wall for the installation of monitoring instrumentation. The objective was to observe and subsequently to reduce ore dilution by monitoring the performance of blasts, the hanging wall movement, as well as the cavity of the open stopes.

Jan 1, 1995

By Paul Worsey, Dave McCool, Ryan Freeman, Chris Wolters, Rick Hines, John Bowles

Carroll Cave, located in Camden County, in south central Missouri, is one of the most significant caves in Missouri with over 12 miles of mapped passages and over 100 known but unmapped side passages. In the early 1990’s there was a breakdown of the originally excellent landowner/caver relations as the ownership of the only known entrance moved to a new generation and grottos squabbled for control. Subsequently the current owner of the natural cave entrance refused to grant anyone permission to enter.

Jan 1, 2003

By David Cole, Paul Cooper, Dale Preece, Jerome Stofleth

The Explosive Destruction System (EDS) has been designed at Sandia National Laboratories for the disposal of chemical munitions (phosgene, mustard gas, sarin etc.), many dating back to World War I. EDS is a portable system that is trailer mounted and consists of a vessel into which a chemical munition can be loaded and opened for neutralization with linear and conical shaped charges. Gases are contained within the sealed chamber. The linear shaped charges split the munition in two and the conical shaped charge (CSC) is aimed at the explosive burster, in each munition, which is detonated by the resulting shaped charge jet, Toxic chemicals remaining in the vessel following detonation are neutralized and disposed of. This paper documents the development of a new CSC needed to reliably detonate explosive bursters in an expanding array of chemical munitions that are beyond what the EDS device was originally designed to eutralize. Design of this new CSC was controlled by the need to deliver energy above the detonation threshold into the explosive after penetrating the outer steel casing, fluid, the burster casing and finally the explosive. Design considerations were driven by jet conditions at the steel/explosive interface inside the burster. Parameters to consider in CSC design include: 1) diameter, 2) liner thickness, 3) liner position in body, 4) explosive weight, and 5) liner shape or interior (apex) angle. The effects of these parameters on final CSC performance are examined in detail. CSC’s that meet the design specifications have been manufactured and tested. The performance of these charges are compared with the original design requirements.

Jan 1, 2002

By Ron Lutz

In today’s world, production is the name of the game. We are all in business to make money. In the Quarrying and Mining industry the same holds true. The primary goal is to develop the best drilling and blasting program available to maintain uniform fragmentation to maximize production. Also we want to maintain drilling and blasting costs and minimize escalators. This paper is intended to discuss ways for all parties (quarry’s, blast service and drill companies) to attain this through understanding what can be done to help blasthole drilling and production. Blast designs and seminar’s emphasize the accuracy of drilling to produce better fragmentation. Blast design must also include basic concepts in the drilling process. The type of drill to be used for example whether it is a crawler or truck mount, top hammer or down the hole is important. Quarry operators have a role to play as well. They hold the key to the production of drilling. What the customer does or does not do has a direct effect financially to the drilling. The phrase of pay me now or pay me latter comes to mind. This paper will explore the detail of planning that is required by the quarry and/or blast service companies before a single hole is drilled. The drill must be able to meet the production need of the operation. The type of drill available and what can and cannot be done. The drill cost must be competitive. This paper will touch on comparison drill costs from 1967 to 1999.

Jan 1, 2000

By Jarrod Bonsmann

"This paper presents the results of small scale testing to examine the effect of various importantparameters on the response of a vehicle due to the detonation of an explosive charge buried inthe soil below the vehicle. In particular, we were interested in examining what effect change instandoff distance, change in mass, and change in surface area would have on the loading applied.We examined the impulse delivered to the target in all cases and for the change in mass andchange in stand-off distance we examined impulse, kinetic energy, and acceleration."

Jan 1, 2012