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By O. Rielo, P. Katsabanis

Traditionally fine aluminum is not used in dry commercial explosives due to the hazard associated with aluminum dust explosions during mixing. An industrial process has been developed which enables the safe use of paint grade Aluminum with ANFO. The addition of fine aluminum particles resulted in increased velocity of detonation of ANFO compositions. Velocities of detonation, in 52mm (2 1/16 in.) diameter confined charges were 20% higher than velocities of detonation of straight ANFO. The detonation performance of fine grained ANFO was not benefited by Al at the diameter tested. Furthermore use of larger Al flakes resulted in decreased velocities of detonation. The results are compatible with the experience of Al addition to high explosives. Tests were also conducted using bio-diesel, finding no substantial difference in the performance of AN fuel explosive compositions which used bio-diesel.

Jan 1, 2009

By Steve Colburn

The CRITERION Survey Systems utilize both theodolite mounted and hand held reflectorless distance meters. These are eye safe, easy-to-use, and specifically designed to endure the harsh environments characteristic to the mining, quarry and explosives industries. Survey data collected by the systems is digitally stored in a ruggedized data collector and then processed with a specialized, Windows-based, interactive software program which can be run on’ any standard PC.

Jan 1, 1998

By Stacy Loizeaux

The Beirut Hilton Hotel, which was built in 1975, but never occupied, was imploded on Sunday, July 14, 2002 by Controlled Demolition, Inc. (CDI) of Phoenix, Maryland and their client, Optimal Engineering Consulting & Contracting, SARL, (OECC) of Antelias, Lebanon to make room for a new hotel. Twenty-seven years ago, just days before the grand opening, the Hilton Hotel became the site of fighting in Lebanon’s Civil War. Christian and Muslim militiamen fought room to room for control of the building and other nearby hotels. The Hilton, two other major hotels and other high-rise buildings were ravaged by the fighting. The building was one of the three major hotels badly damaged, but not rebuilt, in Lebanon. Located in the City Center, the Hilton stood out in a major redevelopment area which, in recent years, had erased the scars of the 15 year long Civil Wa r.

Jan 1, 2003

By David Reddick

The mining industry is in the midst of dramatic change. Mining activities are moving from industrialized first world countries (Canada, Australia, and the United States) to the third world. This shift is occurring due to depleted reserves, tough environmental standards, and expensive labor in traditional mining countries. During a recent trip to South Africa, I was asked, owing to my educational background in economics and an international involvement in drilling and blasting, what changes could be anticipated in third world blasting practices as labor costs increase. It is from that beginning that this presentation has evolved.

Jan 1, 1997

By Tristan Worsey, Nathan Rouse

The Florida legislature allocated funding for the Florida State Fire Marshal (FSFM) to review the applicability of the United States Bureau of Mines (USBM) Report of Investigations (RI) 8507 blast vibration limits with respect to Florida and its soils. The study also discusses whether the current blasting vibration limits set by statute are still appropriate, including a review of measured vibration amplitudes and frequencies, structure responses, and theoretical analyses of material strength and strains

Jan 1, 2019

By Martti Hagfors

The Finnish Defence Forces Technical Research Centre (PVTT) studied the effect of shape of boost-er to its ability to ignite insensitive (IM) plastic bonded explosive (PBX). Therefore an explosive fac-tory produced 20 insensitive (IM) plastic bonded explosive (PBX) charges for the tests. The mass of each of the charges was exactly 9.2 kg (20.3 lb). The charges were equipped by two different type of boosters; RDX and PETN. Both the explosives contained some parts of plasticizers. The weight of all the boosters was exactly 300 g (0.66lb). On the bases of their shape, the boosters were also divid-ed into two different groups, cylindrical and “pancake”. In the middle of the “pancakes” there was also shaped a small cone in such away that the detonation could accelerate to its full speed after the charge was ignited. The following shots were exploded;

Jan 1, 2013

By Thomas L. Barkley

"In early 2015 the Seed Waveform method was used to measure the Geologic response of the MesabiIron Formation to explosives energy input. This single charge wave form was then used to design acritical first blast at a newly developed Taconite mine. This initial blast had several irregular restrictions on design and performance. It had a very unusual “Frying Pan” shape, the regulatory agency required that no fly rock land in State owned waters less than 200 feet (61 m) away, there was no open face to blast to. Design criteria included the need to detonate the blast with two sinking cuts, and have the sinking cuts meet through a narrow neck between the cuts. All these had to be met using a 16 inch (406mm) diameter hole."

Jan 1, 2016

By R. F. Favreau, Patrice Favreau, Dennis Mahan

Cast blasting is becoming more and more popular, not only in coal mines but also in other operations which require excavation of an upper layer of waste rock to uncover temporarily and excavate a layer of ore, which may for example be material for the fertilizer industry.

Jan 1, 2014

By Daniel Hauer

In considering the cost of rock excavation, but little attention has been given to the economical handling and breaking up of boulders. Very few records seem to have been kept as to the cost of such work, and although it is difficult for this reason, to set a fair price for breaking up and handling boulders of various sizes, yet the cost of this detail work enters very materially into the cost of solid rock excavation. The subject is worthy of close and prolonged study.

Jan 1, 2006

By T Barnes, K D. Sexton, T J. Tope

For the past decade, the U.S. Department of Defense (DoD) has been under increasing pressure from state and federal regulatory authorities to develop management strategies for waste streams generated at its bases, installations, and ranges. Since passage of the Federal Facilities Compliance Act (FFCA) in 1992, concerns have focused in particular on military munitions and energetic waste streams.

Jan 1, 1997

By Nick Lewis

Farce Mining of Texas is a surface coal mine located in Laredo, Texas. Farce mines and sells approximately 600,000 tons /year of bituminous coal. A map showing the location of Laredo is provided in Figure 1. As shown, Laredo is located on the border between the United States and Mexico. The mine property runs to the Rio Grande River, the border between the two countries. Farce pumps water from the Rio Grande for use in their coal preparation plant. Laredo’s climate is quite dry with annual rainfall averaging about 12” per year. Also, due to the southern location, Laredo is quite hot. It is common for the temperature to reach 100” F in March and maintain these temperatures through September.

Jan 1, 1994

By John Capers

•The IME is the Safety and Security Association of the commercial explosives industry in the United States and Canada. •Founded in 1913 •Board of Governors •5 Standing committees- 1. Technical 2. Environmental Affairs 3. Legal Affairs 4. Safety & Health 5. Transportation & Distribution

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 L. Wilson, M. Kotzel, T. Pienaar

An empirical equation is presented for the maximum airblast from unconfined charges. This has been tested at a number of sites and with charges ranging from 0.1kg to 311kg. The equation is developed to predict community response to potential explosive test range sites and the testing has added to our knowledge of the effectiveness of mitigating measures. The first site had 10m to 15m high walls that were intended to ameliorate the airblast. These walls functioned to a limited extent and reduced the airblast levels by 2dB to 5dB. The airblast was affected somewhat by topography. Noise levels at the nearest residences exceeded 130dB for charges larger than 1kg, whereas the vibration levels were very small. Formal complaints were received where the airblast level exceeded 128dB as per conventional expectations. Pedestrians and pets in the suburbs were startled by the blasts, emphasizing that the community response is much more sensitive to noise and airblast than vibration levels. The maximum airblast levels were too high for this site to be used on a regular basis. At another site, the airblast levels were significantly increased downwind by up to 10dB due to a moderate wind. A third site, at a quarry, produced unconfined airblast levels beneath the derived limits, but are much higher than the normal quarry blasting. By involving community forums there were no complaints, possibly due to desensitization by the normal blasting activities. The study has highlighted new areas for research in understanding the effect of noise, air blast and vibration on the low cost and informal housing typical in South Africa

Jan 1, 2011

By John Babcock, Gregory Poole, Ron Hudson

In January 2007, Fultondale Alabama opened a new elementary school. Site work at the old school location included blasting activities and the old school building was scheduled for demolition. With help from Apache Construction, blasting was scheduled to be performed in close proximity to the old school building prior to the demolition. Arrangements were made to perform extensive monitoring on the old school building during the blasting activities. The monitoring plan for the project included: • Pre and post blast inspections were performed on the structure; • Conventional crack monitors were installed at 22 locations throughout the structure; • Digital displacement monitors were installed at 6 locations on the structure; and • Seismographs were used to monitor structure vibration at 6 locations and ground vibrations at 9 locations. Blasting activities were allowed to produce vibration levels well above the safe levels established by the U.S. Bureau of Mines (USBM). Vibration levels up to 7.44 in/sec were recorded with no damage noted. Permanent deformation was recorded on vibration levels of 9.68 and above. Not only did this project reinforce previous studies which indicate that concrete block walls can withstand vibration levels well above 2.0 in/sec, this study was also a good example of employing new technology to help determine if/when damage occurs on a specific structure.

Jan 1, 2009

By Takuya Taguchi, Toshihiro Ogata, Atsuio Inoue, Shigeyuki Sasaki

Highly improved drilling machines and mucking machines have been used for the underground construction. To have rapid construction, the roles of blasting operation ha ve been growing more important. At the most tunneling of present, cartridged emulsion explosives have been used for a blasting in Japan. Under this circumstance, a blasting system of ANFO explosives using loading machine has been used recently for a tunnel blasting. However, ANFO has some problems, such as a useless explosives in wet boreholes, bad blasting fumes and the ammonia gas due to the decomposition of ammonium nitrate in contact with the sprayed concrete in tunnel.

Jan 1, 2005

By Dennis R. Jr Bell

Before beginning any site development or mineral extraction activity, it has been well documented that it is first prudent to gain an understanding of the prevailing geologic conditions.Whether it’s identifying the depth to type of bedrock, or determining the quality and quantity of the in place mineral deposit, these factors should always be considered in a project’s fatal flaw analysis. In situations where there is limited subsurface information, geologic models have been proven to be one of the most valuable and cost-effective tools used by the developer and/or his consultant.

Jan 1, 1997

By Chris Breeds, Larry Leone, Jerry Wallace

Project Owners typically require General and Detailed Blast Plans when blasting close to important structures and specify the maximum allowable peak particle velocity for each potentially affected structure. Low, residential level PPV limits may be specified which significantly restricts the potential for blasting to be effectively used. Contractor’s responding to these contract conditions typically cite historic case studies which may, or may not, apply to the specific situation and/or types of structures for which limits have been set. A long submittal cycle typically follows.

Jan 1, 2010

By James A. McGrath

"The predominant key word associated with all commercial blasting methods is “safety”. Safetyshould take precedent over all other aspects of the entire explosives industry which on a wholehas had an excellent track record as to number of injuries per unit of hours worked at all blastsites throughout our country."

Jan 1, 1999

By Alastair C. Torrance

"A brief review of the Australian mining industry is given followed by a more detailed treatment of a study of the influence of primer Size on explosive performance. This is based on a joint research programme conducted by BHP Central Research Laboratories and Dyno Wesfarmers Ltd and examined the effect of the size of cast primers on the run up and steady state detonation velocitiesof ammonium nitrate based explosives as a function of blasthole diameter. The field trials examined a numter of the Dynamo 'Westfarmers HDF series of primers in conjunction with ANFO, emulsion and watergel explosives. Results indicate that the iun up velocity of 187 mm diameter ANFO charges is negligible using cast primers as small as 150g. However, emulsion and watergel explosives did exhibit run up in both 187 and 3:1mm diameter blastholes, independent of the size of primer. This could last from 7 to 10 blashole diameters"

Jan 1, 1991