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By J Lyall Workman, Peter N. Calder

"Large hole rotary drilling is one of the most common methods of producing blastholes in open pitmining. Large hole drilling generally refers to diameters from 9 to 17 inch (229 to 432 mm), however aconsiderable amount of rotary drilling is done in diameters from. 6% to 9 inch (165 to 229 mm). Thesesmaller diameters are especially prevalent in gold mining and quarrying."

Jan 1, 1996

By Jack Eloranta

"This paper compares energy requirements for blasting, crushing and grinding. By tracking electricalconsumption for various powder factors, a general trend has appeared. This study involved over 100million tons of ore and powder factors ranging from .5 lbs/L,T to .8 lb&T. Actual energy usage iscompared to predicted energy based on the Bond equation."

Jan 1, 1998

By Robert Hopler

Some few years ago, when the cruiser “Brooklyn” was passing through the fairway to the southwest of the Battery, the ship being fully equipped with stores, etc., and therefore at her maximum draft, she grounded quite heavily upon some obstruction, and received injuries which necessitated her docking at the Brooklyn navy yard, where extensive repairs had to be made on her damaged bottom.

Jan 1, 2007

By John Haviland, Richard E. Danell

"BHP Australia Coat Pty Ltd (BHPAC) operates seven large open pit coal mines in the Bowen Basin ofCentral Queensland, Australia. These mines have operated for periods ranging from 16 to 37 years. All of these mines have dipping seams to varying degrees and are facing increasing overburden removal in an effort to maintain production. To ensure the economic viability of the operations, this increased level of overburden removal must ah.0 be conducted at lower unit costs."

Jan 1, 1995

By G K. Jorkenson

The SABREX Blast Modelling Program was developed joinlly by the companies of the ICI Explosives Group. of which C-I-L Inc. is a member. SABREX (Scientific Approach to Breaking Rock with Explosives) is a modular computer program which incorporates new technology with a number of tested programs that have been in use world wide.

Jan 1, 1989

By R. Reed Skaggs, William Gault, Douglas Kooker

Both armored personnel carriers and light combat vehicles are increasingly vulnerable to a variety of highly lethal antitank land mines. As a result, there is a need for modeling and understanding the interaction of mine blast products with respect to the resulting loading and damage mechanisms inflicted by explosive blast and impact on vehicle structures. However, the mechanics of blast soil interactions are still poorly understood. The objective of this investigation is to computationally simulate a series of experimental buried mine explosions in saturated sand soil -- over a wide range of scale – and compare the predictions of blast loading to data. Small scale tests have recently been conducted at the University of Maryland with a few grams of RDX acting against an aluminum plate, while recent full-scale tests at ARL involve several kilograms of TNT against 12,500 kg of RHA. The ARL measurements reported here are based on the Vertical Impulse Measurement Fixture (VIMF) facility, a structural mechanical device that responds to blast loading by measuring the vertical displacement of a fixed mass vertical guide rail, which is a direct measure of the imparted impulse. CTH predictions for vertical momentum of the target plate are within 60 – 80 % of the reported impulse data for this wide ranging set of tests. One of the comparisons, however, suggests that the TNT charge in a particular VIMF test may not have fully reacted.

Jan 1, 2005

By Wes Bender

Considering the current interest in Global Positioning System (GPS) usage, it might be timely to look at a more efficient means of utilizing these instruments. The GPS system currently utilizes 28 satellites (4 are spares) circling the earth in an inclined orbit. Normally at least six satellites are within your area of reception at any given time. The satellites broadcast an extremely accurate time signal and an almanac containing all the satellites’ orbital data. This information is updated regularly as the satellites circle the earth. Your GPS receiver, once it has picked up one satellite’s broadcast, can then determine which other satellites should be available for plotting.

Jan 1, 2002

By A. K. Mishra

The mineral industry is leading towards a technology driven optimization process. Drilling and blasting are such unit operations in a mine, which can alter the balance sheet of the mine if not planned properly. The development, improvement and utilisation of innovative technologies in terms of blast monitoring instruments and explosives technology are important for cost effectiveness and safety of mineral industries. The ever-growing demand of mineral has compelled the industry to adopt mega opencast projects with big equipments. This has necessitated use of few hundred tonnes of explosives in each blast. The bulk delivered fourth generation explosives has solved the problem of explosive loading to a large extent. The priming of bulk delivered explosives in Indian mines uses the conventional PETN/TNT based cast boosters. As the conventional cast booster possess safety problems in terms of handling and use, so Indian Explosives Ltd., has developed an emulsion based cast booster (Powergel Boost).

Jan 1, 2005

By Bill Williamson, Doug Richmond, Kerri Kuntz, Gus Gilman, Larry Heywood

This was a description by the poet of what occurred over two centuries earlier to Hannibal’s troops as he passed through the Alps. Interestingly, the pass that many feel is the route that Hannibal chose, Col de la Traversette, is the sight of possibly the earliest avalanche mitigation known. Monastery records describe a tunnel built in 1470, near the top of the pass designed to protect pilgrims from the upper slopes. For the next several centuries, avoidance and reinforced structures were the primary tactics to defend from avalanches

Jan 1, 2009

By Roberto Folchi

"This article deals with the excavation of a tunnel below the town of Isola LIRI, nearFrosinone, in central Italy. The tunnel was driven into a conglomerate formation, of lacustrine_fluvial origins, consisting in carbonate clasts with a sandy_silty matrix and calcitic cement. ""Drilling andblasting"" had to be adopted in place of a tunnel boring machine which had showeduneconomical performances. Good advance speed rates were achieved notwithstanding thepresence of some above structures to safeguard. The nearest structure (an old votivechapel) was less than 10 meters (33 ft.) far from the tunnel crown; the nearest residentialstructure was at about 15 m (49 ft.)."

Jan 1, 1993

By Bruce Vandenberg, Andy Bartfay-Szabo, Steve Conway

Recent advances in solid-state, field portable, fast framing video camera systems and PC based frame capture hardware now allow blast imaging up to 500 frames per second. Up to 8 seconds of data can be stored directly into the unit, downloaded to a PC or archived to a standard VCR without data compression. Since no film processing is involved, motion analysis can be performed instantly and on-site within a few minutes. This paper will describe the design features and applications of the SVClOOO system and compare these with the analogous aspects of film based cameras.

Jan 1, 1995

By P Bellairs

The Hamersley Province is located 1000km 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 Neal Lee, Braden T. Lusk, Brendan McCray

Determining the minimum amount of inert material that can be used between explosive columns is a complex problem. Using too little inert material can result in detonator/primer failure, either by sympathetic detonation of or failure to fire of the subsequent explosive column(s). Propagation type failure results when inert material length between charges is small enough that the subsequent (delayed) deck fires more or less instantly. In this situation, the primer, detonator, or bulk product is initiated by the shock wave from the earlier firing deck. This type of failure may be un-noticed until the vibration/airblast report is examined.

Jan 1, 2016

This paper is concerned with the blasting of rock in mining. The most common purpose of blasting rock is to cast it or to disrupt its structure sufficiently for effective digging and subsequent removal.

Jan 1, 1991

By Richard Hosley, James Daley

Every grey haired member of the explosive’s industry has said at least once, “We have to get some younger blood into our industry, I might want to retire someday.” And many a youngster who loves to see explosions has wondered how to get involved in such an exciting, yet intimidating, industry. While there are many answers to these questions, an internship program is a great answer to both

Jan 1, 2014

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

By George McIvor, Bill Thompson, Don Whitmore, Brad Rhude

"In 1972 Manitoba Hydro decided to develop the hydro electric potential of the Nelson River. This program included the construction of the Jenpeg Generating Station at the point where the channel of the Nelson River discharged into Cross Lake. The Jenpeg station serves two primary functions: 1) Provides a control structure for the regulation of Lake Winnipeg.2) Acts as a 126,000 kilowatt hydraulic generating station."

Jan 1, 1992

By Fumihiko Sumiya, Shinya Tanaka, Yukio Kato, Kenji Tanaka, Tetsuya Sawada

When explosives are heated under an acidic environment due to metal sulfide and sulfuric acidity, their decomposition temperature falls remarkably and decomposition reaction occurs quickly, and then explosives have the risk of the deflagration to the detonation transition. Heat resistant commercial explosives which can be used under conditions of high temperature of 200ºC and an acidic environment were studied. We developed the explosive composition consisted of ammonium perchlorate (AP) as oxidizer, saturated hydrocarbon oil as fuel and binder, and calcium carbonate as decomposition inhibitor. The characteristics of this explosive composition show a heat resistance over 24 hours at 200ºC, and a detonation velocity over 2,500 m s-1. This explosive composition has a cap-sensitivity at temperature higher than 100ºC. Cost effective heat resistant commercial explosives were created by the optimization of the grain size of AP as a main component, the addition of saturated hydrocarbon oil and calcium carbonate, and the control of bulk density by the addition of micro-balloons.

Jan 1, 2003

By Mats Keisu, Bengt Niklasson

The Sofia project has increased the level of knowledge and technique within tunnelling, drifting and contour blasting.

Jan 1, 1992

By Michael Peterson, Robert Davinroy, Robert Rapp, Gregory Hempen, David Herzog, Thomas Keevin

Fish sampling in a deep-water, high velocity, environment is extremely difficult. Conventional techniques such as electro-fishing and netting have been limited to depths generally less than 7 meters (m) and velocities below 1 meter per second (mps). The goal of our study was to sample a bendway weir field on the Mississippi River to assess the effects of the weir field on the fishery. In a bendway weir field, depths can exceed 20 m, and velocities can exceed 3 mps, making conventional sampling techniques inefficient.

Jan 1, 2002