Search Documents

By John C. Brulia

PowerAN is a tradename of Atlas Powder Company for a new line of explosive products comprising blends of emulsion and ANFO in a variety of bulk and packaged grades. The bulk PowerAN grades are either augered or pumped depending upon emulsion content. Augered PowerAN blends contain up to 60% emulsion. Pumped PowerAN grades have an emulsion content of 75% or higher. The blending of PowerAN is usually accomplished at the borehole to satisfy specific borehole conditions. Packaged PowerAN grades are produced in several types of mix plants in diameters of 4" and greater. PowerAN 300 (30% emulsion) and PowerAN 500 (50% emulsion) are the two most popular grades and their chief application is as an economical, high energy replacement for ANFO HD in wet holes. PowerAN combines the cost effectiveness of ANFO with the high performance of emulsions, permitting the blasting engineer to strike an optimum balance between drill pattern expansion and increased productivity according to need.

Jan 1, 1985

By Mario Coderre, Andre Pinsonnault, Francois Lefebvre, Pierre Groleau, Yves Newman, Christian Pouliot

"This paper describes the blasting methods used to excavate the tailrace channel at theLaforge hydroelectric plant. It also shows the importance and versatility of the dopedemulsion explosives used in this project."

Jan 1, 1993

By C W. "Mickey" Bradley

Thunder strikes terror in the hearts of man and has since the advent of time. We all fear the unknown; even the Greeks created a god, THOR, to be responsible for the thunder and rain. Thunder, by itself, can't hurt anyone; it is simply hot air moving very fast. Thunder, however, is caused by lightning and lightning is what we need to fear and rightfully so. Annually, lightning kills hundreds of Americans, injures another 2,000, damages or destroys approximately 30,000 structures, 1 starts thousands of forest fires and strikes mine properties over 100,000 times.

Jan 1, 1992

By Robert B. Hopler

Hercules Incorporated has developed and introduced a totally new non-electric delay blasting cap system which utilizes a low energy gas detonation to activate the caps. Unlike any other initiation system, there is no hole-to-hole connection other than empty plastic tubing until the blast is to be set off. Only at that time, when all personnel and equipment are in the clear, is the special gas mixture introduced through the tubing. The actual time of firing is completely under the control of the operator, by pressing the fire button on the blasting machine.

Jan 1, 1977

By Syed Haq, Kyle Optt, David Campo, Doug Anderson

Limitations on allowable levels of vibration from construction activities generally consider either annoyance or damage. While activities such as drilling and roller compaction primarily create annoyance, the major concern for blasting is usually damage. Many years of research have developed correlations between peak particle velocity and either threshold or structural damage. We emphasize the term “correlation” for two reasons. First, peak particle velocity is only a single-valued representation of a vibration waveform, and does not characterize it completely. Second, a given peak particle velocity by itself, even a particle velocity waveform, will not damage anything – strain does. Why not measure strain all the time? Strain is very localized, and can vary substantially over short distances, so choosing the appropriate strain measurement can be difficult. Measurement of strain is appropriate when either the behavior of a specific structural element is needed, or the overall response of a structure can be adequately represented by a well-selected strain measurement. We will discuss the appropriateness of both particle velocity and strain as deformation and damage descriptors, in general. We will also describe a specific case history, from a tunnel project in New Jersey, correlating strain with peak particle velocity. Finally, we will make recommendations for the choice of measurement type for some common situations.

Jan 1, 2004

By Gungor Tuncer, Ali Kahriman

This paper presents the results of ground vibration measurements carried out in Hisarcik Boron open pit mine located on the west side of the central Anatolia near Kütahya province in Turkey. Within the scope of this study in order to predict peak particle velocity level for this site, ground vibration components were measured for 304 shots during bench blasting. In blasting operations; ANFO (blasting agent), gelatin dynamite (priming) and delay electric detonators (firing) were used as explosives. Parameters of scaled distance (charge quantity per delay and the distance between the source and the station) were recorded carefully and the ground vibration components were measured for all blast events using 2 different types vibration monitors (1 White Mini-Seis and 1 Instantel Minimate Plus Models). The absolute distances between shot points and monitor stations were determined using GPS. The equation of square root scaled distance extensively used in the literature was taken into consideration for the prediction of peak particle velocity.

Jan 1, 2006

By Elias Poulakidas, Marco Arellano

The impact of a higher copper price on the open pit metal mining sector has derived in a faster and safer way in which the mining operation of broken and mineralised material is carried out. In this regard, a good control of bench stability allows a lesser extra removal of material and so more safety to get the planned ore. The stability is ensured through an efficient drilling and blasting, applying the current technology and available know-how. An efficient use of energy through low-density explosives which are the most adequate for the existing solid rock releasing energy in a smoother way through a deterministic detonation sequence which is the application experience presented here. This application experience has two main technological factors; the adequate type of explosive for the kind of rock, in terms of velocity of propagation (Vp) together with the use of a determined detonation sequence and the appropriate designs, which allow to reduce the level of damage to the walls and to maintain a minor backbreaking through quantification with vibration modelling carried out at the near field. The reductions achieved were 30% lower in peak particle velocity.

Jan 1, 2008

By Roger Lucas, Dale Nies

The McLaughlin Mine is an open-pit disseminated gold mining operation. Homestake Mining Company's approach to solving some of the blasting problems inherent to this type of deposit provide an interesting case history. Geology, although unique and site specific, is overall similar to other mines within the Western United States over-thrust belt and demonstrates an excellent example of the blasting conditions and requirements common to most of these operations.

Jan 1, 1990

By Ben Barrett

Dangerous goods, known as hazardous materials in the USA, are subject to special controls during transport to ensure the safety of the public. Dangerous goods are divided into nine classes, and Class 1 is devoted to explosives. Unlike storage or manufacturing, explosive transportation crosses the political boundaries of localities and nations, and its regulation must be centrally managed to avoid duplicate costs of complying with multiple regulations. Additionally, the transport of dangerous goods occurs by four different modes – highway, rail, vessel and air. While each mode has differences which must be addressed, the fundamental principles of classification, packaging, hazard communication and documentation remain the same. When a shipment travels by multiple modes and across borders, consistent regulations become paramount to cost efficiency. This is a common occurrence in the growing global economy.

Jan 1, 2010

By Ruilin Yang

Techniques for the study of blast vibrations, such as monitoring, analysis, and modeling are often misused between near field and far field blast vibrations. This paper discusses the differences between near-field and far-field blast vibrations in terms of these techniques. A typical example of a near-field blast vibration problem is a blast vibration in the crest of a new highwall behind a cast blast. In such a case, the blast can be a couple of hundred feet long and the distance from the blast holes to a monitoring station may only be 100 feet or less. In this situation, the size or spatial geometry of the blast is not negligible compared to the distance from the blast to the vibration monitoring point. On the other hand, a typical example of a far-field blast vibration problem can be a quarry blast with a nearby residence house. In this case, the distance from the blast to the house may be several thousand feet. The size of the blast is less than a couple hundred feet long and negligible compared to the distance from the blast to the vibration monitoring point.

Jan 1, 2007

By Thomas R. Scotese, John L. Ackerman

The Hanging Lake Tunnel Project represents a major portion of the Glenwood Canyon Project, the last piece of Interstate 70 to be constructed. The project features twin bore, large span rock tunnels and six open cut portal excavations, all excavated by drilling and blasting. This paper presents descriptions of the methods used by the Owner and Engineer to control and monitor the drilling and blasting practices in the tunnels and in the portal areas.

Jan 1, 1992

By H J. MacDonald

An Exploding Bridgewire Detonator (EBW) is an explosive initiator which contains only secondary explosives such as PETN and RDX. It is safer than the normal blasting cap because it requires both high electrical energy and a very fast application of that energy to function

Jan 1, 1981

By Andre Pinsonnault, Francois Lefebvre, Yves Newman

In 1989, Les Entreprises Kiewit Ltee signed a C$32 million contract with the Societe d'energie de la Baie James, on behalf of HydroQuebec, to excavate the intake and tailrace channels for a second powerhouse at the LO-2A James Bay hydroelectric project. The multistage contract included removing three marine rock plugs. The first plug was blasted in April 1990. It was a 43 yards wide, triangular shaped wedge that projected into 18 yards of water. Located at the mouth of the intake channel, it contained over 72,000 yd3 of rock, more than twice the 30,000 yd3 found in most rock plugs.

Jan 1, 1991

By Alexander S. Escalante, Luis R. Ramirez, Nelson A. Arostegui

Research, analyze, discuss, design, and build an electric oven to perform one of the quality control tests the fanel or common fulminers to determine what temperatures they can detonate at. Give practical applications, conclusions, recommendations and bibliography.

Feb 1, 2020

By Don Rapp, Rufus Flinchum

Air blast and flyrock are two of the most critical concerns facing the blaster of today. This paper will provide the blaster with proven procedures for recognizing open face and bench surface problems, explain various surveying methods, and provide the mathematical formulas for calculating and designing proper hole placement and explosive load configuration. A concept called "Pattern Footage" is utilized in conjunction with a USBM study to develop blast designs aimed at minimizing air blast and flyrock. In addition to this main focus, this concept can be used in shot displacement and cast blasting design.

Jan 1, 1993

By J Foklesi, G Bohus, D Benedek

The breakage process in blasting takes place in space and in time and the latter will determine the degree of fragmentation, shape of the muckpile and the extent of displacement. The shock wave travels at the velocity of sound in the material and it can easily be measured. The cracks' velocity is only 0.38 % of the velocity of sound. The number of cracks at any distance from the explosion cavity, their length and the time of development can be calculated.

Jan 1, 1986

By M. L. Mendes, J. Q. Nojiri, S. C. Botelho, A. P. Campanha

In February 28, 2001 JOULE coordinated the first tests with an electronic detonator in South America at an iron ore operation - ITABIRA MINES from the Brazilian COMPANHIA VALE DO RIO DOCE (CVRD) - the largest producer and exporter of iron ore in the world. ITABIRA MINES (CAU and CONCEI O) belong to one of the complexes, called the Southern System, producing 56 million tons of ROM as well as concentrated products and pellets. This paper is going to describe the tests at ITABIRA MINES with results indicating the improvement in the excavator productivity and reduction of the mining global costs (due to the better performance of the equipment and potential reduction of the maintenance cost).

Jan 1, 2002

By Raymond Hofstetter, Paul Worsey

The purpose of this paper is to investigate commonly used methods for mitigating the effects of shrapnel from linear shape charges (LSC) used in the demolition industry. Primarily the problem is not that shrapnel poses a threat to human bystanders, but rather it can affect the other charges in the demolition or damage to structures in close proximity to the charges. This research aims to determine what methods have success at stopping shrapnel, what methods do not, and to promote an awareness of the dangers of using the LSC without any protection. The project was carried out at the Experimental Mine site at the Missouri University of Science and Technology. This research is an undergraduate research project to fulfill the requirements for the Explosives Engineering minor program at MST.

Jan 1, 2008

By Jason Baird, Seokbin Lim

Run up is a factor in Linear Shaped Charge (LSC) cutting for which an account must be made. It occurs on the initiation segment of the charge, and the cutting performance during this period is significantly lower. Previous investigations by the UMR Explosives Group observed that similar effects occur not only with LSCs but a wide range of other explosives applications, including explosive-driven flux-compression generators. Prior to this investigation, it was believed that the main contributing factors to run up were from the combined effects of explosive run up (detonation pressure), lack of confinement at the free, initiation end of the charge, and penetrator transition from segmented pieces to a long-rod penetrator blade. As an initial step to understanding the mechanics of LSC run up, a series of investigations was performed in which the testing series was divided into several sub-categories (explosive detonation pressure run up, lack of confinement and long-rod penetrator concept) in order to reveal the effect of each on the run up. Predominantly, commercially manufactured LSCs were used for the investigation, and the entire testing was completed by the UMR Explosives Group.

Jan 1, 2006

By R Vuolio, B A. Jonsson

In the center of Helsinki - capital of Finland - extensive blasting operations were carried out during the years 1982 - 84. At the corner of the streets Mannerheimintie and Simonkatu - in the Forum block - about 125,000 cu.m. of rock were blasted to give place for a new modern shopping centre (Fig. 1). Added to this amount of rock another 10,000 cu.m. were blasted for a transport tunnel to an adjacent underground bombshelter (Fig.2) which is to be used as a parking place in peace-time. The blasting work was demanding and difficult to carry out due to old buildings surrounding the work-site as well as computers and other sensitive equipment installed in some of them.

Jan 1, 1985