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By David Cole, Paul Cooper, Dale Preece, Jerome Stofleth

The Explosive Destruction System (EDS) has been designed at Sandia National Laboratories for the disposal of chemical munitions (phosgene, mustard gas, sarin etc.), many dating back to World War I. EDS is a portable system that is trailer mounted and consists of a vessel into which a chemical munition can be loaded and opened for neutralization with linear and conical shaped charges. Gases are contained within the sealed chamber. The linear shaped charges split the munition in two and the conical shaped charge (CSC) is aimed at the explosive burster, in each munition, which is detonated by the resulting shaped charge jet, Toxic chemicals remaining in the vessel following detonation are neutralized and disposed of. This paper documents the development of a new CSC needed to reliably detonate explosive bursters in an expanding array of chemical munitions that are beyond what the EDS device was originally designed to eutralize. Design of this new CSC was controlled by the need to deliver energy above the detonation threshold into the explosive after penetrating the outer steel casing, fluid, the burster casing and finally the explosive. Design considerations were driven by jet conditions at the steel/explosive interface inside the burster. Parameters to consider in CSC design include: 1) diameter, 2) liner thickness, 3) liner position in body, 4) explosive weight, and 5) liner shape or interior (apex) angle. The effects of these parameters on final CSC performance are examined in detail. CSC’s that meet the design specifications have been manufactured and tested. The performance of these charges are compared with the original design requirements.

Jan 1, 2002

By N/A N/A

Aw a rd winners from the University of MissouriRolla. Back row from left: Seok Bin Lim, Chris B o l l i n g e r, Adam Kre s l e r, Scott Geer, Joseph Cohn, and James (Buck) Hawkins; Front ro w f rom left: Dr. Worsey, Trish Robertson, and Fio G i a n a

Jan 1, 2004

By Stephen H. Chung

The SABREX computer blast simulation program permits the study of the effective use of explosive energies and predicts the total performance of a blast in terms of:fragment size distribution: muckpile profile; breakage at grade, column and collar with respect to the control case; crack penetration; damage envelope behind and beneath blastholes; a complete cost analysis including explosives, drilling and accessory costs

Jan 1, 1995

By Mark William Withey

"Blasting safety in surface mining is a necessary industrial goal. Proper techniques and disciplinesexercised during the blasting process enhance the probability of achieving that goal.The blasting process is generally a series of repetitive steps performed by all blasting technicians.Because habits formed during this process influence safety, production and cost, proper habitsbecome compulsory."

Jan 1, 1995

By Randall M. Wheeler

Many of us have used a seismograph to measure peak particle velocity and frequency. But do we really understand why? Also, why do we measure particle velocity instead of displacement and/or acceleration? What is the vector sum? How do these items relate? Where does frequency fit in? This workshop will attempt to answer these and other questions. Some of the answers may surprise you, others may not.

Jan 1, 1997

By Alex Chapman, Cam Thomas, Bryan Karney

"During the early summer of 1989, Ontario Hydro removed a concrete portion of the North Channel Dam at Crystal Falls Generating Station by blasting and excavating in marine conditions. Because of the severity of underwater blasting and because the site was in close proximity to the replacement dam, there was concern that hydraulic shock waves generated by the detonation could damage either the new dam or its control structures. This paper examines the data associated with the hydraulic shock waves generated by underwater blasting, and studies the effectiveness of an air curtain in reducing the peak pressures. In previous trials using the air curtain technique, a rule-of-thumb factor was used to estimate that only 10% of the original pressure pulse would propagate across the air curtain. However, this value had little basis in theory. A theoretical formulation of the problem by Karney in 1989 indicated a provisional value of 0.18 for this factor, but was heavily dependent on confirmation from in-field testing. Data provided by Ontario Hydro from an actual blasting procedure indicate that a more conservative value of 0.32 may be more appropriate. Thus.although the air curtain did provide considerable reduction of peak pressures, the data at Crystal Falls indicates its performance was below the anticipated level. However, due to problems with the instrumentation and some inconsistencies in the resulting data. it is recommended that this value be further refined as additional data become available."

Jan 1, 1992

By Enrique Albarrán, Julian Hernández

"In 1942 The “Presa Mixcoac” dam was built, along with 15 other dams, to control the rain fall waterin the mountains west of Mexico City. Mexico City’s population at that time was around 1.5 millionpeople, and the dam was way out of the city."

Jan 1, 2016

By Teele Tuuna, Voglers Eesti OÜ

Blasting operations are a strong and important part in any kind of building and mining industry, a shot-firer profession is one of the oldest professions in the civilized world. It still serves an important and ongoing purpose in the modern economy all over the world. Europe, nowadays, values strongly the mobility of workers, the movement of know-how and labor force between different countries inside Europe. There are no borders for most of the everyday professions.

Jan 1, 2018

By Robert Hopler

As a part of the depression and rectification work on the Port Morris branch of the Harlem Division of the New York Central & Hudson River Railroad, a short tunnel is being driven under St. Mary’s Park. The park is near 149th St. and St. Ann’s Ave., in the Borough of the Bronx, New York City.

Jan 1, 2006

By Michael Mann

Two house trailers and a modem modular house, all pillar-supported with cantilevered perimeters, were monitored for structural response to vibrations from surface coal mine blasts. Due to the large blast site distances, peak particle velocities measured in the ground beside the houses did not exceed 0.32 ips, and airblasts did not exceed 106 dB. However, the structures responded significantly to the ground vibrations, with maximum high-comer amplification factors as high as 8.5 in the horizontal directions. Vertical structural responses were as high as 10 times the vertical peak particle velocities in the ground, but appeared to be driven more by horizontal ground motions. No measurable airblast responses were observed. The natural frequencies of the structures ranged from 5 to 10 Hz.

Jan 1, 2000

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 Steve Dillingham

Today, a typical blaster is likely to wear many hats, including, but not limited to, supervisor, risk manager, safety coordinator, explosives engineer, communicator, as well as professional decision maker. Simply put, a blaster in the new millennium is an all encompassing blast site manager. As you know, accidents on the blast site can range from blast crew injuries to blasting incidents resulting from vibration, flyrock, misfires, etc. Not surprising, the incidents can quite often be traced back to direct preventable human action on the blast site. They can, however, frequently be avoided, if responsibly identified early and managed properly by an efficient blast site manager. Your company cannot afford to simply employ blasters; good blast site managers are necessary to produce the safest results possible.

Jan 1, 2001

Choosing the correct delay time for many blasting applications is an important and critical blast design parameter for controlling fragmentation, muckpile shape, swell, digability, throw, ground vibration and airblast. BAl and its affiliates have monitored thousands of full scale blasts in a variety of field conditions, spanning over 15 countries, with sophisticated blast monitoring instrumentation. In some blast environments, a small change in the choice of delay times used had a dramatic and pronounced effect on the overall blast results. In other blast environments, large changes in the choice of delays used had absolutely no effect on the final results in terms of specific outputs. In environments which were sensitive to the delay selection, the type of explosive, dynamic response time of the rock mass (TMIN), integrity of the material, burden and rock mass geometry, all played a very important ,role.

Jan 1, 1998

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 Steve Dillingham

Here in the United States, as well as around the world, pose a daily dilemma - to wash or not to wash. Let’s face it, all trucks, especially our industry work horses - bulk trucks - get dirty. We all know that these units can be very expensive and washing them keeps your business investment looking new, improves public relations, fuels company pride, and facilitates equipment safety and preventative maintenance inspections.

Jan 1, 2001

By Jim Mikelait

Overview ?? Why do we need security? ?? Needs assessment ?? Elements to any security system ?? Protect, Detect, Alert, esponse ?? 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 Thierry Bernard, J. M. Laboz

2000 HIGH-TECH SEMINAR Blasting Technology, Instrumentation and Explosives Applications

Jan 1, 2000

By Dale S. Preece

"Detonation delay timing has been an important aspect of quality rock blasting for decades. Detonators that enable delay timing have improved over the years especially with the recent advent of precision electronic detonators. The positive effects of precision delay timing have been observed repeatedly in the field with improved fragmentation, heave and overall blast control. Three-dimensional computational capabilities in terms of software, material models and computer speed have recently made possible the computer simulation of multiple blast holes in a bench configuration with precise delay timing between holes. Some of the key physical phenomena enabled by precise delay timing include: 1) collision and interaction of stress waves produced by adjacent blast holes, 2) reinforcement of stress waves from multiple holes as they reflect from the bench face and ground surface, 3) reflection of stress waves from “dynamic free surfaces” created by previously detonating holes, and 4) deformation induced fracturing, cracking and fragmentation. Simulating rock blasting in 3D has shed light on the physics involved and is resulting in an evolution of our understanding of fragmentation mechanisms. Routine use of these 3D computational tools will result in a much better understanding of the complex physics set in motion by the rock blasting process and allow predictionof improved blasting."

Jan 1, 2009

By Frank Sames

The control of the environmental effects, especially blast vibration and airblast, has become a dominating planning criterion for most surface blasting operations. Compliance with existing regulations is generally achieved through constraints in the blast design, or monitoring programs. Commonly, blast vibration and airblast signals are rated and compared only by their maximum amplitude and the principal frequency associated with the peak.

Jan 1, 1997

By Randall S. Marks

Bonneville Dam, completed in 1938, included the smallest and busiest lock on the Columbia and Snake River Navigation System. To expedite barge traffic through this restriction, a new larger lock was designed and contracted by the U.S. Army Corp of Engineers.

Jan 1, 1997