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By Don Novotny, Dana Spencer

In this workshop our intent is quite simple; that is that we will introduce a relatively new technology that may have applications in blasting applications. This technology is the laser initiation of explosives. This workshop course is not intended to suggest ways in which specific blasting problems can be resolved. That is the purview of experts within each of your fields.

Jan 1, 1994

By Robert B. Hopler

The hazards which naturally prevail in underground coal mines, always severe and unpredictable due to the loosely-consolidated strata in which coal is frequently found, are increased by the commonly-occurring combination of coal dust, methane, and explosives. It was recognized by the mid-nineteenth century that coal dust was the basic factor contributing to disastrous explosions killing hundreds of miners, and that the ignition of methane gas was often the source of the coal dust explosions. It was apparent that preventing the ignition of methane was a critical part of avoiding these disasters, and it was also apparent that one cause of such ignitions was the firing of explosives. In addition, it was found that dust explosions were often initiated by blown-out shots of explosives in the absence of methane.

Jan 1, 1996

By Satish Kate

Indian limestone mines which are highly mechanized in operation and supply limestone to the cement plants have been quite successful in devising ways and means to optimize blasting parameters, so as to have best fragmentation, powder factor, and cost of excavation. In primary blasting mechanized or manually mixed ammonium nitrate Fuel Oil is quite popular in dry holes, and in case of watery holes conventional packaged slurry/emulsions are being used. In order to avail the low density characteristics of the ANFO, some limestone mines have also used Saw Dust and Rice Husk along with ANFO. A number of field trials have been undertaken to explore the suitability of mixing rice-husk and saw dust with ANFO. Presently, about 10% of rice husk/saw dust is being used only to expand the explosive column. The main technical consideration for the use of saw dust/rice husk, has been to reduce the final density and increase the occupancy of explosive in the blast-hole. This not only lowers the detonation pressure in the blast holes, but also reduces cost of explosive without compromising on the fragmentation quality. Besides, with sleeping of the charge there is no substantial fall in the blast quality.

Jan 1, 2006

By David P. Reddick

"Suncor Inc. Oilsands Group mining operation in Northern Alberta, Canada, has been blasting to loosen the oilsands to increase production and decrease maintenance of the bucketwheel excavators for over twenty years. In 1991 an area of the mine was encountered which had a working face of 130 feet rather than the usual 20 to 57. In order to maintain production objectives, the planning and blasting departments of the mine took on the task of blasting as much of the working face as possible. McGinnis Rathole Drilling Company provided the drilling for the project and Mining Services International (MSI) delivered the bulk explosives to the boreholes. It is believed the resultingblasts exceeded several known records in production blasting."

Jan 1, 1992

By John Dean Smith

In order to discuss problem solving techniques for the future. we must first review the past. This paper will discuss the drilling and blasting problems and techniques that were used by .Imax Coal in the past few years, tn those of today.

Jan 1, 1991

By S A. Steyn, P Terrett

Air decking has become a widely practised method internationally for modifying fragmentation results and providing cost savings from reduced explosive consumption. Duvha has been applying air deck technology to overburden and midburden blasting for a few years. A thorough evaluation of air decking at Duvha has been made by instrumenting a number of blasts and analysing costs from direct savings in reduced explosives costs to savings in improved dragline productivity.

Jan 1, 1995

By Charles O'Connor, Ben Tisa

International Training Resources is a company consisting of personnel with extensive law enforcement and military special operations experience, The staff members are qualified to train and certify, assist and advise law enforcement officers and agencies, at any level, in critical incident policy, procedures and tactical resolutions. Successful critical incident resolution is comprised of many elements of professional skills and personnel. (Command staff, negotiators, snipers, tactical teams, uniform patrol, K-9, bomb squad, etc.) Recently, tactical teams have been developing the capability for the use of explosive methods for rapid entry into crisis locations. This document ‘will briefly describe the environment, operational issues and courses of action associated with developing a complete tactical breaching program for utilization by SWAT teams in response to operational conditions in critical incident situations. This topic is being presented to the I.S.E.E. evaluators under “Interesting Blasting Projects” and “Public Relations” categories. Tactical operations differ significantly from traditional industry practices and we appreciate the opportunity to show the industry other professional applications of explosive materials and techniques. Presently, of the few schools from which law enforcement officers can receive training with explosive breaching methods, International Training Resources is the only company currently teaching and certifying officers which has received total endorsement by the California Peace Officer’s Standards and Training Commission (P.O.S.T.) and the state blaster’s licensing commission. We have pioneered the combining of law enforcement needs and blasting industry technology to train tactical officers, nationwide, in the mission essential skills necessary for explosive breaching.

Jan 1, 2000

By B Mohanty, Y C. Lizotte

Optimization of blast fragmentation in underground hardrock mining requires analysis of its effects on loading and haulage equipment, together with the downstream materials handling system, with the objective of minimizing total mine operating costs. A methodology is reported which has been developed to quantify the actual fragmentation and equipment performance in the field. This is data which has seldom been practicable to capture nor received serious attention in mines. Based upon the experience gained in underground studies, a prototype standard is proposed which aims to summarize the pertinent data, collection and analysis for fragmentation assessment. This relates to parameters of direct measure, such as mean size and distribution, as well as muckpile and work environment. The paper concludes by defining the impact of fragmentation on the loading and downstream handling system.

Jan 1, 1991

By Martti Hagfors

UNDERWATER EXPLOSIONS - Part 6 - EFFCTS OF CYLINDERICAL SHAPE OF CHARGE TO THE RESULTS OF ENERGY MEASUREMENTS OF EXPLOSIVES

Jan 1, 2008

By Roger Holmberg, Donald Jonson

The Swedish Standard SS 460 48 66, “Vibration and shock - guidance levels for blasting induced vibration limits”, is based on more than 50 years of experience from blasting close to structures and tunnels. The Swedish Standard gives a method for calculation of guidance values for different types of buildings and ground condition under the building. This is done for every building and structure within a predetermined zone. The guidance levels are for the peak particle velocity monitored in vertical direction. The standard is valid for all kinds of blasting project (tunnelling, quarrying, mining etc.) The guidance levels neither take in to consideration discomfort for people inside the building or structure nor vibration sensitive equipment inside the structure. The paper also presents the Swedish Standard SS 02521 “Vibration and shock - Blast induced airborne shock wave - Guidance levels for buildings”.

Jan 1, 2005

By V. Wetzig

In the past, various investigations have been carried out at the Hagerbach Experimental Gallery under accurately reproducible conditions, in order to determine the emissions emanating from blasting operations. Comparative investigations proved that the composition of the blast fumes is influenced by the choice of different explosives. It also emerged that the use of emulsion explosives leads to significantly lower concentrations of harmful substances in the blast fumes. Further investigations concerned the residues and reaction products from the explosive process which are left in the debris. Eluate tests on representative samples of debris were used to determine the concentrations of nitrate, nitrite and ammonium in the debris.

Jan 1, 2001

By Jerry Wallace

This project consisted of blasting for expansion of a major interstate natural gas transmission pipeline pump station. The pump station handled 400-500 million cubic feet (1 l- 14 million cubic meters) of gas per day.

Jan 1, 1996

By David P. Reddick

Economics is a social science dealing with the allocation of scarce resources. In modern times the “science” was identified by Adam Smith in his book, The Wealth of Nations, written in 1776. Mr.Smith, highly influenced by the Mercantilists of the 17th and 18th centuries, identified the “Invisible Hand” which would lead every individual to pursue selfish rewards in purchasing goods. He speculated these selfish motives would result in the best good for all. Price would be determined by barter, at a point where self-centered customers and vendors were mutually satisfied. Today, Smith’s theory is known throughout the world as “Capitalism” but most often termed “Free Enterprise” in the United States.

Jan 1, 1992

By Lance McAnuff

The year 2001 coincided with the forty-fifth year of blasting-control specialization by the author. Commencing with the construction of the Saint Lawrence Seaway System in 1956 and continuing until the present time this career has spanned one of the most progressive and exciting periods in the still relatively short history of commercial blasting. The paper touches upon a number of the more interesting projects with which the writer was involved during those early days, including the removal by explosives of “Ripple Rock” the infamous underwater hazard to shipping which at one time inhibited ocean traffic along the Inside Passage between Vancouver Island and the mainland of British Columbia, Canada’s most westerly province. Various assignments involving incidents from devastatingly ,tragic to comically absurd are described, along with personalities encountered along the away, most of them readily recognizable as giants in the field of explosives engineering. Various stages in the evolution of state-of-the-art explosive products, initiation systems vibration monitoring equipment and limiting criteria are compared and some of the effects these have had on safety and productivity during the last forty-five years are analyzed.

Jan 1, 2002

By Larry Schneider

"0 ne of the incentives that led to the development of non-electric shock tube initiation systems was the desire within the industry to improve detonator safety. And to the extent that nonelectric initiators are immune to the hazards of stray current and radio frequency energy found on normal blast sites, an advancement in safety has been accomplished. However, as a cautionary note, it is important to realize that there are still many hazards associated with any initiation system. While some of these hazards may differ from those associated with electric detonators, others are identical to those associated with any type of initiation system. For instance, contrary to what some uninformedblasters may believe, lightning remains a hazard when using nonelectric initiation as well as electric initiation."

Jan 1, 1995

By Rundqvist

The best method to minimise disturbances from traffic to the neighbourhood and in Urban is probably to go underground. For obvious reasons this will cause vibrations, noise and other environmental effects which need very strict regulations and quality assurance in order to complete the work successfully. One project is “Southern Link”, a part of a ring road system. The system of tunnels includes 16 kilometres of tunnels right beneath the south part of the city of Stockholm. At least 20.000 people will be or could be affected by different kinds of disturbances and pollution such as vibrations, noise, gas and groundwater. Another project is the “Arlanda Link”. A new railway with three stations has been built under the existing and running to Arlanda airport with its terminals. Authorities have carefully judged these projects, which cause complaints from neighbours due to disturbances. The blasting operations are professionally managed by the contractors and controlled by consultants to keep the regulations according to the Swedish standards, which are well described in the tender documents by risk analysis and technical descriptions. In spite of that, one conclusion is that it is not always possible to go underground without exceeding stipulated regulations with existing technique. Some of the regulations also double the cost of excavation

Jan 1, 2001

By M Ash, P Bellairs

The world class iron ore mines at Mt Whaleback, Tom Price and Paraburdoo located in the Hamersley Province of Western Australia must mine the Mt McRae Shale to obtain high grade ore from the Dales Gorge Member of the Brockman Iron Formation. The Mt McRae Shale contains a Black Pyritic Shale lithology that reacts with Ammonium Nitrate based explosives. This paper provides an overview of the problems associated with mining this reactive rock type as well as the development of a comprehensive procedure to safely and efficiently blast, excavate and dispose of this material.

Jan 1, 1995

By Bruce Notthup

Using a Three Dimensional Laser Profiler, persomrel from Austin Powder were able to determine drilling patterns for use in underground mine Room and Pillar blasting operations, The faces had got out of alignment, causing concave faces across the 100 feet wide, 28 feet high tunnels. This was leading to poor drilling and poor blasting results. By profiling the faces, modifications could be made to the drilling pattern to help gradually straighten the faces. The Laser Profiler was also used to check the accuracy of collaring the holes and also perform post blast surveying of the positions of the bootlegs. This allowed recommendations to be made to improve drilling operations at the face. In addition, other volumetric calculations could be performed using the systems’ surveying software, all a lot more easily and quickly than by standard methods.

Jan 1, 1994

By R. Singh, M. Roy, D. Singh

Success of a blasting pattern in Blasting-off-the-solid (BOS) in Bord (Room) & Pillar method of coal mining is judged by the percentage of pull achieved vis-à-vis the yield of coal produced in a blasted round. Improper blast design and distribution of explosives in shot holes normally causes poor breakage i.e. a major portion of shot holes left unbroken resulting into reduced yield per blast. Over and above the disturbance to the roof is also due to excessive vibration caused by explosive energy not properly utilized in fragmentation.

Jan 1, 2003

By Detnet Solutions

1. “Daisy-Chain” concept The term “daisy-chain” stems from the fact that when the HotShot? detonators are connected there is a chain or electrical path for electrical current to flow from detonator A to detonator B, detonator B to detonator C etc until the path is terminated by an electrical means. The “daisy-chain” concept has long been used in electronic detonator systems, historically used in Expert Explosives’ ExEx 1000 5/6 wire system and currently in use in African Explosives Limited (AEL’s) Electrodet? electronic detonator system and has been adopted as the basis upon which the “auto-programmability” of the HotShot? electronic detonator system functions. HotShot? Detonators are connected to each other in a string, completing a “daisy chain”, and during the auto-detection mode of the control equipment, it is possible for the equipment to determine the order of hookup of the detonators as well as map the entire blast layout. The auxiliary components (Row Controllers & Branch Controllers) assist the control equipment in mapping the entire blast by indicating different points on the blast, i.e. The inflection point of a row of blast holes on a closed chevron timing pattern, the beginning of row of blast holes on open chevron timing pattern and extra blast holes or extra blast rows.

Jan 1, 2004