Search Documents

By A Lance McAnuff, Robert T. Booren

Construction of a dock facility for the Lake Erie Development Project of Stelco Steel involved underwater blasting in commercial fishing waters near Port Dover, Ontario. The most stringent environmental constraints were imposed and a monitoring program involving water overpressure recordings, using equipment developed specifically for this assignment, correlated with observation of caged fish specimens at various distances from the blast source, was undertaken to determine the effects on fish life and to establish whether a protective air-bubble curtain system should be installed around each blast area.

Jan 1, 1989

By W. J. Birch, R. Farnfield, G. D. Rangel-Sharp

It is widely recognised that complaints from members of the public relating to blasting operations are related to both ground vibration and air overpressure. It is also known that a complaint is more likely to be generated if the person is inside of a structure at the time of the blast. Reports relating to such complaints often refer to ‘noise’ inside the structure with terms like ‘rattling’ commonly being employed. Such acoustic response is widely perceived within the blasting industry to be directly related to high levels of air overpressure although there appears to have been very little research carried out specifically related to this effect.

Jan 1, 2007

By Zuhair Ibrahim, Dan Tillema, Ali Reza

This paper details the investigation of a fatal explosion that occurred on April 8, 2011 at a magazine used to store fireworks in Waikele, HI. The fireworks had been confiscated by the Bureau of Immigrations and Customs Enforcement after they were informed that a container shipped to the United States contained illegal fireworks. Four groups of cardboard cartons that were marked as 1.4G (consumer fireworks) were determined to be consistent with the more explosive 1.3G type, commercial display fireworks. The subcontractor retained to destroy these fireworks stored the shipment in the subject magazine and was in the process of disassembling them on the day the explosion occurred.

Jan 1, 2014

By R. Franfield, W. J. Birch, L. Bermingham

Previous researchers have put forward two different theories as to the origin of air overpressure from quarry blasting. In 1980, Siskind et al postulated that the initial face movement gave rise to the displacement of air and that this resulted in the air overpressure pulse. However in 1990 McKenzie et al carried out research that indicated that the air overpressure pulse came into being as consequence of the shock wave created by the detention of the explosive charge in a blast hole, rapidly propagating through the rock and then impacting on the quarry face.

Jan 1, 2013

By John Brennan

Necessity, they say, is the mother of invention. Certainly that sentiment held true during the early stages of explosive engineering. While seaside forts were concerned over static ignition of their black powder caches in the 14th century1, the mining industry in the 1800s were plagued by accidents surrounding the ignition methods for their black powder blasts.

Jan 1, 2011

By Lewis L. Oriard

This paper describes the process of developing blasting specifications for 850 miles of new pipe trench running parallel to an existing high-pressure gas pipeline, often with as little as 14 ft to the existing pipeline trench. The primary method of preventing damage to the existing pipeline was the use of fracture (overbreak) control.

Jan 1, 1994

By S. Mandal, R. Singh

The demolition of structures with explosive though most rapid, safe and efficient requires planned blast design parameters with respect to geometric and strength properties of the structure to be demolished. The paper, here deals with successtil demolition of three old bridge piers by different blast designs. These piers were 11 m tall and very close to the existing bridge, The plan distance of the old piers from the existing bridge varied between 43 m and 14,25 m. The paper also deals with the mathematical concepts for the causes of such action of demolition/dismantling of structures.

Jan 1, 2001

By Terry L. Cook

RAG Coal West, Inc., Belle Ayr Mine is located in the heart of Wyoming’s rich Powder River Basin coalfield. Belle Ayr utilizes an open pit, truck/shovel operation to strip the overburden off the 70’seam of sub bituminous coal. Our excavation capacities consist of a 301 Marion with a bucket size of 52 cubic yards, and a 4100 XPB P&H with a capacity of 76 cubic yards. Production levels on these machines are closely monitored utilizing the Modular Mining Dispatch system. RAG Coal West, Inc. is a coal mining business that utilizes the effectiveness of teams as one of their strategies. Technicians have a certain amount of control over their own Team Process. The Drilling & Blasting Team is an assortment of blasters with varying experience levels. We have been able to think outside of the box when it comes to certain “proven” methods of blasting.

Jan 1, 2004

By G J. Kulbieda

The Empire Mine initiated production in 1963. Since then the unit operations of drilling and blasting have evolved continually in order to meet the increased mining requirements demanded by plant expansions in 1968, 1973 and 1980. Additionally, advance mine planning has become an integral part of proper pit development and is necessary to insure uniform blending of the distinct ore horizons contained within the mine area. Blasting practices have been modified to facilitate the autogenous grinding system utilized at Empire and pioneered in the Iron Ore Industry. Technical innovations in the explosives industry, as well as, progress regarding on site blast engineering methods have substantially increased the use of ammonium nitrate explosives and helped to establish efficient charging procedures. In addition, the recent introduction and use of ammonium nitrate fueled with nitropropane and methanol indicates that it is a viable substitute for aluminized ANFO.

Jan 1, 1981

By P Bellairs

The Hamersley Province is located 1OOOkm to the North of Perth .the Capital City of Western Australia and is of major economic significance due to the mining of extensive deposits of Haematitic Iron Ore for both domestic and export use. A small but significant proportion of the waste associated with these deposits presents problems due to its ability to spontaneously combust and react with explosives resulting in premature detonations.

Jan 1, 1996

By Leslie Taylor, R. Reed Skagga, William Gault

The ultimate aim of our overall task, of which the effort described in this paper is a part, is to be able to model the impulsive output of buried charges and the response of targets of interest. It is not practical or cost-effective to determine the response of all targets of interest to buried charges of all sizes by testing them. In order to have confidence in our models, however, they must be validated by a modest number of tests. A critical element in modeling the response of a target is the ability to model the loading function. The load a buried charge applies to a target above it when the charge detonates can be characterized in terms of the vertical impulse. The vertical impulse is a function of the size of the charge, its depth of burial, and the properties of the soil in which it is buried. The primary objective of the effort described in this paper is to determine the load a known charge places on a non-responding target so the data can be used to validate our models.

Jan 1, 2005

By R J. Roach, D Roy

After months of discussion on ways and means to improve productivity in the shaft sinking process, it was decided to look at those areas where, historically, methods have been stagnant for many years. These categories included drilling, hole diameter, drill patterns, explosive types, explosive loads, initiation techniques, cut design, wall control, fragmentation and heated magazines.

Jan 1, 1997

By B H. A Brown

The components of passive laser survey systems and their relative functions are presented. A general outline of the capabilities and the information available are followed by two case histories. These involve the use of such systems in quarry blasts where loading adjustments and drilling designs were required. Their application in blast casting operations, stockpile measurement, surface and underground construction, and general surveying areas are briefly covered, with comments on the potential for demonstrating a return on an investment in laser survey equipment.

Jan 1, 1990

By John M. Bolger, Keith E. McMaster

Excessive salt fines are undesirable in underground salt mining as they are considered a costly waste by-product. This paper describes an extensive explosive application program conducted at The Canadian Salt Company Ltd, located in Pugwash, Nova Scotia, Canada. The prime objective of the program was to reduce the quantity of fines generated from this company's underground production blasts. The program was known as the "The Fines Reduction Program".

Jan 1, 1996

By Roger L. McCarthy, Ali Reza

The use of an ammonium nitrate-fuel oil (ANFO) explosive in the Oklahoma City Federal Building bombing has led to a renewed interest in using additives during the manufacturing process of ammonium nitrate to render it non-detonable. Suggested additives include calcium carbonate, which is already used in some European countries, and mono-ammonium phosphate (MAP) or di-ammonium phosphate (DAP), which are the primary desensitizing agents claimed in US patent 3,366,468, Method for desensitizing fertilizer grade ammonium nitrate and the product obtained, issued Jan. 30, 1968 (Porter, 1965).

Jan 1, 1999

By P Cotton, N Cox

The Brisbane City Council has implemented a program of continual improvement at its Mount Coot-tha Quarry in the heart of Brisbane, Australia. The program has been underway for the past 6 years, and has resulted in very significant improvements in terms of both the cost effectiveness of its operation, and in terms of its environmental impact on nearby residents. The work has included a focus, amongst other things, on blasting efficiency, and has challenged conventional thinking in terms of the size of blasts fired, the frequency of firing, the diameter of blastholes, and the use of bulk emulsion or slurry explosives.

Jan 1, 1995

By David Willock, S. Singh, Michael Glogger

The efficiency of the loading system in a mine depends upon the characteristics of the muck pile, the loading machine specifications and the loading practices. The focus of this paper was to look specifically at the size distribution of blasted material, and to quantify its effects on loader productivity. A scale model of LHD was designed and fabricated to represent machines currently employed in the industry. The experiments were performed using crushed Gabbro, which was mixed in various proportions according to Rossin-Rammler size distribution to give five different characteristic particle sizes and five different size distribution constants for each characteristic particle size. The effect of the size distribution constant on peak and mean penetration forces, work done and bucket fill factor was examined. In addition, the influence of mean particle size, 80% passing size (D80) and % oversize on the penetration force and bucket load was investigated.

Jan 1, 2001

By Conny Sjoberg, Finn Ouchterlony, Bjorn Jonsson

This contribution reports an investigation of the blasting damage in the contour of an access ramp to a Swedish underground laboratory for nuclear waste related studies. Near zone vibration measurements were made for 7 rounds and the results converted to a site specific scaling law. A simple engineering correction for the influence of the charge length wee developed and the resulting equations used to predict the damage zone depths of three different drilling and charging patterns.

Jan 1, 1993

By Jeff Wachendorf

As the title implies, this paper details the start of a cast blasting and the design flexibility required to satisfy different parameters encountered on a large coal mine employing cast blasting as the program has grown and evolved around the town of Colstrip, Montana. As strip ratios have increased, the need to adapt and find solutions to provide coal at a reasonable cost to the mine mouth power plants has risen. Colstrip, Montana has a long history of coal mining which dates back to the early 1920s when Foley Brothers began supplying coal strictly for powering locomotive engines.

Jan 1, 2015

By Paul Worsey, Matthew K. Coy

New blasting mat designs are currently tested in the field on actual blasting jobs and only undergo qualitative rather than quantitative assessment. The majority of matted blasting occurs in trenching in which the blast designs and field conditions vary considerably. In order to assess a new blasting mat material and design, a new standard test was devised.

Jan 1, 2015