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By Jim Mikelait

?? Why do we need security? ?? Needs assessment ?? Elements to any security system ?? Protect, Detect, Alert, Response ?? Electronic Security System Criteria ?? Advantages and Limitations of Various Security Options ?? Internal measures to protect against potentially harmful employees ?? How can technology improve my business?

Jan 1, 2006

By R Mancini

Explosive charge action on the medium is intrinsically dynamic (fast rising and fast vanishing). On the contrary, information available on rock strength is drawn from static behaviour, and it's commonly used to characterise the rock, even in blasting problems.

Jan 1, 1995

By Michael David Wilkins, Paul N. Worsey

Little research has been published on stemming blast holes, particularly what happens during the process. Previous work has concentrated on the performance of the inert material to find the best way to seal the hole and retain the explosive energy, at the exclusion of determining what happens during the loading and stemming process.

Jan 1, 1998

By T S. Bajpayee, Thomas C. Ruhe

"The Pittsburgh Research Laboratory of NIOSH conducted research to determine the safe operatingconditions for using recycled (used) lubricating oil from mining equipment as a partial replacement for diesel fuel to make ANFO-type blasting agents. The use of recycled oil (RO) conserves energy, reduces oil imports, and reduces mining costs."

Jan 1, 1999

By Thomas M. Keevin, Gregory L. Hempen

Accurate assessment of blasting near an object (organism or structure) requires recording of the damage parameter for low-valued scaled distances. Seismograph recordings of particle velocity are a well established, common procedure for land-based blasting. Similarly, pressure recording of the absolute waveform needs to be a more common procedure for sensitive, underwater resources.

Jan 1, 1997

By Liu Hui Yang Nianhua Feng Shuyu

The paper analyzed the dynamic stress in the rock around the tunnel and the effect on the stress variation for the different blasting parameters. Also, the paper verified the theoretical results by dynamic photoelastical tests and provided helpful reference for the design of blasting near a tunnel.

Jan 1, 1998

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 Calvin J. Konya

For proper blast design, one must make the assumption that all blastholes release nearly ideal energy. In many types of blasting operations, blastholes release very little useful energy. These blastholes are called malfunctioning blastholes. Recent studies indicate that as many as 30 percent of all blastholes are malfunctioning. These malfunctioning blastholes are not an unusual occurrence.

Jan 1, 1988

By Michael S. Stern, Gordon P. McDonald

The increasing costs and problems associated with transporting and safely disposing of used engine oils from remote mine sites have caused mining companies to consider other ways to consume their used oil. One practical method of disposing of these used oils is to blend them with the diesel component of ANFO and Heavy ANFO type explosives.

Jan 1, 1993

By Paul Miller, Rene Laprade

Does a 76 mm Ø hole drilled over 45 m deep remain straight? This is the question asked by the Engineering department at Placer Dome's Dome Mine in Timmins, Ontario before they could lay out the initiation sequence in a long-hole production stope. Everyone realized that the holes would wander over such great depths, but it was important to know where they went.

Jan 1, 1998

By Kai Nielsen

Drilling and blasting design results in a fragmentation that will have an important economic influence on all subsequent operations such as loading, transport secondary blasting and primary crushing.

Jan 1, 1987

By Robert C. Friend

On-the-job and "hands-on" training programs which attempt to train newcomers to blasting with instructors whose only qualification is their experience can easily miss the boat. Organized training programs which utilize competent instructors and a well developed format are necessary if we wish to provide a meaningful program of instruction, But, let's not go overboard and attempt to provide a level of training which goes far beyond the scope of the worker's duties and responsibilities, and "need to know",

Jan 1, 1980

By Richard N. Snyder

In this system for connecting blasting caps to the initiation source, the need for a redundant design structure provides more reliable method of explosive initiation. This is accomplished by using a complete system starting at the blasting control, through the initiation line structure through the initiation line and connecting blocks to the blasting cap. The connecting structure between the initiation device and the blasting caps may be connecting blocks or other means.

Jan 1, 1995

In this paper, the author points out the need to beware of simple time correlations as proof of cause and effect when comparing building cracks and blasting operations. There is a need to be aware of the many other causes besides blasting which affect buildings. Some of these have histories of cyclic behavior; others have a long-term increasing effect on aging and deterioration, often with poorly defined time histories. Many are so strongly site specific that generic relationships are difficult to quantify.

Jan 1, 1981

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 Charles W. Trettel

Confined explosives upon detonation produce a chemical reaction generating expanding gases that result in fragmentation of matrix a chemical to mechanical transition. A 100% energy conversion during transition is difficult, if not impossible, to achieve. There are numerous variables that affect energy transition. Although fragmentation is the most often used criteria to determine shot efficiency, the escaping energy profile provides additional data as to the efficiency of a blast. Escaping energy can also have deleterious effects in the form of ground motion.

Jan 1, 1975

By Chen Aiping, Wei Banyun, Chen Canchang

"The gaseous explosives consisting of combustible gas and combustion-supporting gas wereused in the opening end of a steel pipe and the ignition was in the closed end of the pipeusing continuous air feed within the permissible length limit of industrial equipment, theexperimental results show the mechanisms of forced transition from combustion todetonation and what is the effective equipment for the transition."

Jan 1, 1993

By Norman Disley, David B. Counter, Lionel Hebert

Misfires in underground and surface production blasts can be costly. Costs can arise from loss of resource, production interruptions, having to redrill or otherwise refire the blast (a hazardous process at best), due to added secondary blasting or breakage, and/or from increased LHD maintenance costs attributable to poor fragmentation.

Jan 1, 1996

By Frank Sames

Blast vibration and airblast overpressure signals are generally rated and compared only by their maximum amplitude and the principal frequency associated with the peak pulse. The scaled distance concept is often used to predict peak amplitudes and can be applied for blasts in the same area of a mine to evaluate the statistical properties of a set of readings.

Jan 1, 1997

By D P. Onag, B Mohanty

AECL Research (AECL) has constructed an Underground Research Laboratory (URL) as a facility for research and development in the Canadian Nuclear Fuel Waste Management Program. The objectives of the program are to develop and evaluate the technology to ensure safe, permanent disposal of Canada's nuclear fuel waste. Several multidisciplinary experiments and engineering demonstrations are planned for the URL over the next ten years.

Jan 1, 1991