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By Nils Heinke, Stephen M. Collinsorth

To anyone who is responsible for the production of blast holes, who is looked to on a daily basis for drill maintenance and performance, whose bottom line may depend on the survival of the mine itself.. How much awareness should one have on such things that truly impact production, maintenance and overall job cost? Do you know your drill’s maximum capacity?

Jan 1, 1998

By Lon Santis, Michael Swisdak, David Leidel, John Tatom

The Institute of Makers of Explosives (IME) and A-P-T Research, Inc (APT) have developed and released a quantitative risk management tool, IMESAFR (IME Safety Analysis For Risk), for the commercial explosives industry. Consequence algorithms in IMESAFR are considered state-of-the-art. Generally, they mirror those in SAFER (US Department of Defense Explosives Safety Board quantitative risk management software). The science behind the software has now been assessed for its maturity. Results have identified areas where additional test consequence data could improve predictions. To address these areas, full-scale testing programs to provide the needed data have been formulated. Proposed testing efforts include work to: (1) improve characterization of explosive articles now absent from SAFER, and (2) refine modeling of the Potential Explosion Site (PES) types, particularly small metal structures, also not found in SAFER. Goals of each program as well as requirements for conducting the tests have been established. Testing results are to be used to improve the algorithms and to further the state-of-the-art in risk-based explosives safety.

Jan 1, 2012

By Daniel Roy

This paper introduces a new, safer bulk emulsion loading system for underground mining operations. The features and benefits of the equipment, along with the use of Dyno Nobel Inc. patented gassed emulsion technology, is summarized in the application of a stope blast with very difficult and complex ground conditions. The paper describes methods used to optimize the amount of energy required to break the ore while protecting the integrity of the surrounding backfilled pillar.

Jan 1, 2003

By Agne Rustan

The 9th International Symposium on Rock Fragmentation by Blasting was held in the Granada Conference Centre, Granada, Spain from the 14th - 17th September 2009. The Symposium was preceded by a 1 ½ day Workshop on “Vibrations from Blasting” organized by the initiator Dr. Alex Spathis and his colleague M. J. Noy, both employed at Orica Mining, Australia. Prof. Josè Sanchidrian at the “Universidad Politécnic de Madrid” in Madrid, Spain was the main organizer for both the Workshop and the Symposium. A record number of participants came (292) from a record number of countries (41). There were a total of 14 papers in the Vibrations from Blasting Seminar and 96 papers and 2 Keynote Addresses in the Fragblast 9 Symposium itself. The aim with this paper is to present some results from Fragblast 9 which are of interest for a large target group. One very important result from the Fragblast 9 meeting was that it was decided there that Fragblast 10 will be held in November 2012 New Delhi India.

Jan 1, 2009

By Gennaro Di Lauro, Laura Meraviglia, Demostenes Efstratiadis, Danilo Coppe

This paper presentation regards the European Union’s project “I.C.E.A. - Identification Colors of Explosives and Blasting Accessories (Agreement number – HOME/2010/ISEC/AG/071 – 30 – CE – 0447240/00-11), submitted under the call for proposal “ISEC 2010 ACTION GRANT” of the “Prevention and Fight against Crime” Program of European Commission. The main objective of the project is to simplify counter-terrorism security measures and the procedures for visual identification of blasting devices.

Jan 1, 2015

By James L. Austing, Allen J. Tulis, Ronald Pape, Ronald G. Draftz

In a certain sense, the explosives industry began in the 13th century with the invention of black powder, which is an intimate mixture of sulfur, carbon black or charcoal, and potassium or sodium nitrate. For several centuries thereafter, black powder was the sole general purpose energetic material, serving as an igniter, propelling charge, bursting charge, and blasting agent. By today’s standards, black powder is totally inadequate for the latter three functions, but its use continues as an igniter for propellant charges because of its unique ability to ignite and burn under ambient conditions. The history of the development of black powder was reviewed by Rose (1980).

Jan 1, 1995

By Grigor Mishev, Georgi Petrov, Benjamin Cebrian

Before designing a single blast or all the blasts on a pit level, it is critical to assess the main goal on each. To do this, a series of constraints must be taken into account: wall protection, vibration control, flyrock hazards, fragmentation required, desired displacement as well as economy, equipment efficiency. The tool to do this is the Blast Master Plan. Many mines fail to integrate on its elaboration key stakeholders such as planning, operations, geology/geotechnical and milling departments. Designs not only have to provide consistent behavior of the blasts, but have to make sense all in one with the geological and geotechnical conditions as a starting point. Once blasts are designed under an organized set of priorities, and complemented with quality controls, optimization is possible on a large scale.

Jan 1, 2016

By Robert Martin, Brian W. Stump, David P. Anderson

2We use field measurements to quantify physical processes that accompany different types of mining explosions. The data sets collected include three-component ground motion, acoustic, video and high speed film, three dimensional topography, geological and geophysical properties, design blast pattern and timing, and velocity of detonation in the explosive for individual borehole detonation times. The explosions include simple single-fired contained explosions, ones designed to bulk and fracture material and those that cast material. Our goal is a physical understanding of these sources for the purposes of optimizing blasting practices.

Jan 1, 1998

To meet the energy requirements, hydroelectric projects are planned and executed in many countries. Though these projects requires a high capital investment, the returns are regular with minimum maintenance after commissioning of the project and are ecofriendly. Bhutan is situated in the eastern Himalayas and covers an area of 38,394km2 (14824.01sq. miles. It is bordered by India in East, South and West and by Tibet in the North. The hydropower potential of the country is estimated at 30,000MW, out of which around 5% has been harnessed.

Jan 1, 2016

By Crazy Horse - The Journal of Explosives Engineering - Vol 20 No 1

The crew at Crazy Horse Memorial has produced a w o n d e rful new video called “The Fine Art of Mountain Carving.” The video closely examines for the first time, the extraordinary explosives engineering on the Crazy Horse mountain currently in pro g ress in the Black Hills of South Dakota. The 56-minute video takes the viewer up the mountain for a behind-the-scenes look at the drilling and blasting crew at work on the mountain. The video was written, edited and produced by Robb D e Wall and is available exclusively from the Crazy Horse Memorial in both DVD and VHS formats. For i n f o rmation, see www.crazyhorsememorial.org The following, is a brief summary of the 25 steps involved in carving the mountain. The video goes into extensive detail on each of the 25 steps. Both those in the explosives industry and those outside the industry will find the video intere s t i n g .

Jan 1, 2004

By Per-Anders Persson

This chapter deals with the concepts ofshock waves aud detonation waves together, because a detonation wave is really a shock wave, supported by the explosive reaction that the shock wave ignites and propagates as it travels through the explosive material. In the context of rock blasting, furthermore, there is justification for treating shock waves and detonation waves together, because the mechanical effect of the detonation in an explosive in a drillhole in rock is propagated and its effects are spread throughout the surrounding rock by means of a shock wave The overall performance of an explosive in rock blasting or any other application is of course dependent on how much thermal energy is released in the chemical reaction that occurs when the material detonates, and on how much useful mrc!~amcal work the reaction products can do as they expand. A major portion of this chapter deals with the prediction and measurement of explosive performance, a subject which is now still in a process of rapid development.

Jan 1, 1994

By Robert Hopler

This article, advocating having employees whose specific job would be to fire blasts in underground coal mines in llinois, was written 5 years prior to the establishment of the U.S. Bureau of Mines, and 2 1/2 years before the worst month in U.S. coal mining history, when 692 miners were killed in three separate explosions in December 1907. Obviously something had to be done to improve safety in the use of explosives, and having dedicated shotfirers was a good first step.

Jan 1, 2006

By P Geddes, K Grohs, C K. McKenzie, M Morrish

Low grade surface gold mining at the Acacia Resources, Union Reefs Gold Mine in Australia's Northern Territory, involves the excavation of benches in three slices after blasting. Blast patterns span zones of high and low grade ore, as well as zones of waste, and selective excavation is required in order to maintain economical head grades for the carbon-in-leach processing plant.

Jan 1, 1998

By Brian Gar Wingfield

"The introduction of the QuarryMan laser profile system in 1987, along with the development of the corresponding 3-D software, gave a qualified operator pertinent information about dimensions of quarry highwalls, pattern and hole loading design, stockpile profiles, etc . . . Attributes helpful for this endeavor included surveying, computer, and blasting knowledge. Since not all operators had theseskills, a simpler model, the QuarryAce, was designed to look a t highwall dimensions in 2-D view . Al though less sophisticated than the QuarryMan instrument and its software, it is simpler to instruct in its use and has the ability to determine burdens at different depth levels . An in-house user f r i e n d l y computer program was designed to utilize QuarryAce depth vs. burden data . This program was created to enable laser and computer novices to generate information useful to the everyday blaster."

Jan 1, 1992

By David M. Langlais, Krystle Pelham

"Explosives used in blasting operations, natural and anthropogenic sources such as septic systems,fertilizers, and decomposing vegetation can potentially contaminate groundwater with nitrate in thevicinity of construction sites and make identification of blasting impacts difficult. Blasting operationsfor a private construction project in Windham, New Hampshire were indicated as the source of water quality impacts to private drinking water wells prompting the New Hampshire Department ofTransportation (NHDOT) to implement a proactive approach to limit the potential for impacts fromblasting for ongoing NHDOT projects. NHDOT has developed a baseline drinking water monitoringprogram designed to detect potential impacts and to ensure alternative drinking water is providedthroughout the construction phase of projects. In 2013, the U.S. Geological Survey (USGS) andNHDOT began a study to determine the source and fate of nitrogen compounds near blasting sites using a combination of isotopic, time series, geochemical, hydrologic, and geologic data. Approximately 1.75 million cubic yards (1.33 cubic meters) of rock were removed by blasting in several locations for roadway construction at a major highway construction site in southern New Hampshire."

Jan 1, 2016

By Doug Bartley, Roy McKinstry, John Floyd

In March of 2001, Barrick Goldstrike became the first surface gold operation in North America to evaluate the advantages of electronic detonators. A detailed study was conducted to quantify the benefits of the use of electronic detonators to the downstream excavation, crushing and ore processing operations. The following methods were used to quantify blast performance:

Jan 1, 2003

By B Mohanty, G Yamin

A number of parameters, aside from blast design and pre-existing rock conditions, can change the performance of the explosives system in actual blasting practice. Sympathetic pressures caused by detonation of preceding holes have been identified as a major contributor to explosive system malfunctions, leading to uneven blasting performance. These effects can occur both within a hole or across several holes. These can consist of high transient pressures related to the shock phase of the explosion or the relatively longer or quasi-static pressures associated with the explosion gas expansion phase. This study presents the findings from an on- going investigation on measurement and analysis of these pressures between donor and receptor holes in a granitic outcrop for representative inter-hole distances and borehole conditions, employing single cartridges of emulsion explosive in 45 mm diameter holes. The results, despite wide scatter in the measured values, show the very short duration pressures to range up to 7 MPa and arriving within a few milliseconds after detonation, whereas the much lower amplitude pressures arrive after tens of milliseconds. Both have the potential to seriously affect the performance of an explosives system.

Jan 1, 2005

By Frank Sames

Most Blasting Programs are developed focussing on the environmental impact with respect to blast vibration and airblast. Compliance with existing regulations or policies limiting the immissions are generally achieved through constrains in the blast design, or monitoring programs. Efficient monitoring programs combine compliance monitoring and blast assessment. Signals, which are obtained in the area of direct influence of the seismic source, can contain valuable information about the blast design parameters. Techniques to analyze blast vibration signals have advanced and can assist in understanding the contribution of individual blast parameters to blast vibration and airblast. Advanced signal analysis encompasses magnitude analysis, Fast Fourier Transforms (FFT) and frequency scans in the frequency domain, as well as filtering in the time domain. Through examples, the advanced signal analysis techniques and their limitations are described and discussed, showing the impact of blast timing, timing accuracy, charge configuration and the geology dependent transmission behavior. Optimization criteria and pragmatic monitoring programs can be developed on the basis of the most influential blast parameters. In addition, however, safety and the cost efficiency of the blasting program are essential to the success of an operation. That is where advanced signal analysis techniques can interface with blast planning, computer assisted modeling and information systems. A valuable process can be developed to ensure compliance with existing regulations and efficient risk management for mining operations, while tracking cost and supporting operational decisions. A conceptual blasting information system is presented.

Jan 1, 2000

By James H. Owen

Because of price structure, ANFO is normally considered to be the most cost effective explosive used in quarry blasting. Results indicate that bulk smulsion can be more cost effective in applications where hole sizes range up to 6.5 inches in diameter while providing the simplicity of single product loading and storage. This can be accomplished without any fragmentation and/or movement loss usually in patterns which are about twice the size of ANFO patterns, allowing the combined drilling and blasting cost to be less when using bulk emulsions. Examples are presented supporting this concept using actual field results along with some simple calculations which take into account differences in the products such as density, matrix and detonation velocity.

Jan 1, 1998

By R. F. Favreau, Patrice Favreau

In many quarries and construction sites visited by the authors over the last 50 years, the latter have observed muck piles from blasting with explosives, which included numerous large blocks, in some cases of dimensions larger than the input to the crusher. The names of these sites cannot be given in the article because the owners insist that data obtained on such visits be kept confidential. Often the blasters felt that the natural fissures in the rock would compensate for the use of a low powder factor, and they asked the authors to explain why such blocks were present. A detailed analysis of the situation often indicated that the cause of the blocks is that explained by figures such as 6 and 7 below in the article.

Jan 1, 2018