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By Andre Pienaar, Larry Wilson, Clive Dawkins

The development of implementation of cost effective emulsion explosive and portable pumping system for the replacement of package explosives in the deep level gold mining environment. A number of versions of portable pumps will be presented, demonstrating continuous improvement on these systems. Data on reliability of units in the field will be presented.

Jan 1, 2009

By D Schneider, H Elliott

The advantages and disadvantages of using inclined boreholes in blasting has been under discussion for a long time. Some recognized disadvantages are that drilling costs, both operating and capital costs, are higher for inclined holes than for vertical ones, and that drilling accuracy is more difficult to maintain. People who have used angled holes in practice, on the other hand, have claimed that the quality of blast results was improved. In fact, their popularity has increased, especially in Australia.

Jan 1, 1988

By Jerry W. Schweiker

An extensive computer program has been developed which will store and analyze pertinent blast related parameters such as date, time, shot coordinates, charge, delay times, etc. In conjunction with these blast parameters, measured ground vibration information can be stored. In addition to actual seismograph data, predicted ground vibration in terms of velocity (inches/sec) can be generated for selected receiver locations. The magnitude of the blast generated ground vibration is based on scale distance relationships. The program can be used for planning blasts, to satisfy local environmental regulations and for insurance and/or legal purposes.

Jan 1, 1984

By John J. Ridgeway

Habits take us where we were yesterday and attitudes tend to keep us there. Until recently, little had been accomplished to improve conventional explosive energy for use offshore. But with the special requirements of the Offshore Oil Industry, and particularly in the North Sea, most equipment, products and services must be specialized as well. Previous attempts to excavate a trench for a sealine in surf areas had been impossible to accomplish. But with the application of safe, controlled explosive energy, an impossible task to accomplish yesterday has now become a reality. Explosive energy, often overlooked as a convenient and economical offshore tool, excavated a clean trench underwater for a 40" sealine at Djeno in the African Congo recently.

Jan 1, 1977

By D O. Doehring, W A. Charlie, W A. Lewis

The detonation of explosive charges releases large quantities of energy that can produce rock and soil deformations far from the detonation point Extensive data are available on blasting in general and on the performance of certain structures subjected to blast vibrations. However, only limited information is available on the performance of earthfill dams and other hydraulic structures subjected to blasting. The limited data indicate that, whatever the cause, one or several cycles of repeated strains in earthfill dams may cause residual porewater pressure increases. Limiting the peak particle velocity to less than 2.5 cm/s for operating dams constructed of or having foundations consisting of saturated, loose sands or silts and to less than 5 cm/s for other earthfill dams, should keep strains below the threshold strains required for residual porewater pressure increases to occur. Porewater pressures should be monitored throughout a blasting operation, and they should be allowed to dissipate, if necessary, before subsequent charges are detonated.

Jan 1, 1987

By Catherine T. Aimone

A series of experiments have been performed to characterize fragmentation and microcracking in quartz monzonite copper porphyry. The flyer plate impact method was used to generate plane shock waves in rock specimens for impact pressures between 1.6 and 7.3 GPa and impact pulse durations between 1.1 and 7.0 µs. The effects of pressures up to 4.8 GPa and pulse duration on fragment size distributions and microcrack densities were studied. The results show that pressures effect particle sizes to a greater extent at higher pulse durations. However, changes in pressure and pulse duration show little influence on the density of microcracks induced during explosive loading. These results indicate that the nucleation and growth of microcracks in rock subjected to shock waves occur uniformly throughout. A substantial decrease in particle sizes for high pulse durations is attributed to more time allowed for microcracks to grow and coalesce, forming individual particles.

Jan 1, 1985

By Chuck Kliche, Bill Clements

This project involved the removal of the top of an old water supply reservoir tank for the City of Lead, SD by explosives. The general contract called for the removal of the concrete top without damaging the sides or floor of the reservoir. The option of a rock hammer was eliminated, due to the possibility of an unpredictable collapse damaging the sides or floor of the reservoir. Different blasting options were discussed between the primary contractor and the blasting contractor, along with the pros and cons of each. The primary contractor settled on the option of drilling the structure for blasting versus using shaped charges

Jan 1, 2007

By Thomas E. Ricketts

Limited void volume blasting (LVVB) occurs when rock is blasted into a volume that is not sufficient to let the rock expand to its free-bulking value. The freebulking value is obtained when the rock particles have enough space to separate, tumble and rotate to produce the maximum amount of void possible between the fragments when they finally come to rest. Although bulking value depends on particle size distribution and shape, a typical free-bulking value for uniform, finely broken shale is about 1.67. LVVB occurs in almost every type of blasting used in both surface and underground mining operations. For example, in multiple-row bench blasting for surface mining, the final delays that are designed to fragment the rock furthest from the free-face are generally confined by previously blasted rock which results in a LVVB situation. In underground mining, the blasting is automatically confined and is commonly done intentionally to limited void volume to reduce mining cost and improve safety. LVVB primarily affects rubble bulking and thus the excavation of the broken rock which is related to the productivity and economics of a mining operation.

Jan 1, 1989

By A. S. Tawadrous

The stress field around a detonating charge in a borehole was calculated using AUTODYN for a variety of in-situ stress conditions. Calculations were conducted for zero in-situ stress, hydrostatic conditions at 100MPa, uniaxial stress conditions of 100MPa, and bi-axial state of stress with amplitudes of 200MPa and 100MPa along the axes. Two different explosives, ANFO and emulsion, were used for the calculations. It was shown that in-situ stress fields had an effect on the tensile and compressional damage zones around the blasthole, calculated on the basis of the maximum amplitude of the stress pulses in the rock after the detonation of the explosive in the blasthole. The extent of compressional damage increased around the borehole, whereas, the extent of the tensile damage decreased. The damage zones are of elliptical nature with their axes parallel to the direction of the principal stresses. The difference between the major and minor axis of the elliptical damage was not very significant in the case of the compressional damage; however it was significant in the case of the tensile damage.

Jan 1, 2007

By Lon Santis

This paper describes several applications of quantitative risk assessment in the management of commercial explosives operations. The Institute of Makers of Explosives’ (IME) quantitative risk assessment software modeling program IMESAFR was used for this analysis. Modeled activities include the unloading of a ship at port, locating a safe haven, and dealing with encroachment on a manufacturing facility. The layout of actual explosives sites were used for the analysis. The risk of fatality is analyzed and shown it can be used to make informed operational decisions for each activity. A study of the risks to individuals from activities involving commercial explosives compared to individual risks from other daily activities or exposures is also presented.

Jan 1, 2008

By Paul Schmiesing, Matt Higgins

Central Oregon is a fast growing resort community centered in Bend, Oregon. Bend is bordered by the Cascade Mountains to the west and the high dessert to the east. Central Oregon is blanketed with lava rock with little topsoil. Ditch blasting is a staple in the area. Almost all utilities excavation (gas lines, sewer lines, water lines, and electrical lines) requires blasting. There is also a considerable amount of blasting required for site excavations and drywells. On average, there are over 500 blasts per year in Bend alone. All of this blasting is done using small holes, generally 2.5 inches in diameter. Typical ditches will have 200 holes, between 2-3 rows wide, with an average depth of 8 feet, and on 36 inch centers. Almost all shots are dry. Successful blasting requires careful control of drilling and loading. The vesicular basalt contains numerous lava tubes and caves making drilling and loading difficult. The rock conditions vary greatly from one side of town to the other requiring different powder factors and different scale of distances for vibration control. Caret%1 calculations of vibration predictions and use of site-specific seismic info is necessary. Marry shots will require deck loading and careful timing to ensure one-charge per delay. It is an every day occurrence to be blasting near residential and commercial structures or high pressure gas lines. Many times ditch blasting will incorporate excavation blasting. The different hole patterns used for the ditches and the excavation shots presents challenging timing sequences.

Jan 1, 2000

By David Harrison, Brian Harrison

The Army Corps of Engineers completed the Charleroi Lock and Dam in 1932. It is located on the Monongahela river approximately 22 miles (35k) south of Pittsburgh in Charleroi, Pennsylvania. It is comprised of a 420-foot (128m) gated dam, and a 720-foot (219m) by 56-foot (17m) land side lock, which provides for a 16.6 foot (5m) vertical lift.

Jan 1, 2018

By Harry Verakis, Thomas Lobb

This paper summarizes the course of mine blasting safety, particularly in underground coal mining, in the USA for over a century of mining operations. During the late 1800's and especially in the first decade of the 1900's, a large number of mine explosions occurred in which blasting played a significant role. A contributor to the large number of mine explosions during this time period was the use of black blasting powder to extract coal and other minerals. A review is made of some of the more significant underground coal mine explosions that resulted from blasting operations during this time period up to the present day. The safety measures that were adopted and required by a series of laws as a result of mine explosion disasters in which blasting was one of the factors are examined. The time line of historical improvements in blasting safety and the tremendous reduction in fatalities and injuries over a century is illustrated and discussed. The improvements, which included the elimination of black powder and dynamite and the introduction of safer explosives termed "permissibles" occurred slowly over time and culminated from the occurrence of many coal mine explosion disasters. The blasting accident history over the past decade is discussed to show the great gains made when compared to the first decade of the 1900's. The most recent blasting accident fatality that occurred in October 2006 at a U.S. underground coal mine is also discussed. Although the blasting accident record is significantly improved from over a century ago, continual improvement is needed to reach the goal of zero fatalities.

Jan 1, 2009

By Kevin Phelps, Jason Baird, Philip Mulligan, Dominique Nolan

The basic metric for linear shaped charge performance is the amount of cutting distance that the charge can effectively yield given a specific standoff and target. Due to its size and restricted production runs the 10,500 grain/foot (2,232.25 grams/meter) linear shaped charge has had only limited studies that examine cutting performance and standoff. This article covers research regarding cutting performance verses standoff as the charge is applied to common structural steel. Specifically this study uses A36 mild carbon structural steel blocks of 10.16 cm by 11.80 cm by 35.56 cm and standoff distances of 0.5, 1.0, 1.5, and 2.0 charge diameters. Data presented includes the presentation of actual cutting performance numbers, comparison of that data to projected performance based on currently recognized industry guidelines, and a discussion of what may contribute to the performance found in this study.

Jan 1, 2013

By R Frank Chiappeta, Eduardo Nixon, John Dean Smith, Tom Treleaven

"The creation of the Panama Canal was far more than a vast, unprecedented feat of engineering. It was a profoundly important historic event and a sweeping human drama not unlike that of war. Apart from wars, it represented the largest, most costly single effort ever before mounted anywhere on earth. It held the world's attention over a span of forty years. It affected the lives of tens of thousands of people at every level of society and of virtually every race and nationality. Great reputations were made and destroyed. For numbers of men and women it was the adventure of a lifetime.

Jan 1, 1998

By Terry Nichols, Karl E: Warkwick Burgher, Charles J. Wideman

The application of Fourier spectral analysis to records of ground vibration generated by over 100 explosions from an open pit mine is used to develop empirical predictor equations that relate the response spectra to the blasting parameters used to generate the excitation motion. Time series representations of ground particle velocity are transformed into the frequency domain where the appropriate modifications are made such that the inverse Fourier transform yields the time series representation of particle displacement and acceleration. Compensations are made for the transform function of the recording system in the frequency domain. Spectral analysis of the three types of ground motion is correlated with the blasting parameters. The results show that the frequency content of ground vibrations generated from a mine blast can be quantified in terms of the predictor equations.

Jan 1, 1990

By Italo Onederra, Jason Furtney, Ewan Sellers

The Hybrid Stress Blasting Model (HSBM) is a high level blast modelling research tool which provides results that can still be used implicitly for practical blast design. The code is being developed through an international collaborative research project funded by a consortium of companies which is comprised of explosive, equipment suppliers and major mining houses. A key component of the HSBM is the numerical code and user interface designated as Blo-Up 2.5. To date validation work has focussed on breakage, fragmentation and damage outcomes in controlled laboratory experiments and using large concrete cubes

Jan 1, 2012

By P. E. Hoffman, Joshua Ph. D.

The Institute of Makers of Explosives (IME) led a post-detonation debris collection project in conjunction with a large AN railcar detonation conducted by the Department of Homeland SecurityTransportation Security Administration, Department of Defense-Combating Terrorism Technical Support Office, Sandia National Laboratories, and the U.S. Army Dugway Proving Grounds. This important work will aid in underpinning algorithms used in the IMESAFR (Institute of Makers of Explosives Safety Analysis for Risk) Quantitative Risk Assessment (QRA) tool. The test also provided valuable data about AN detonation characteristics when it is driven to detonation. The test took place at the Utah Dugway Proving Grounds (DPG) on April 27, 2018 and the debris collection was conducted the following two weeks with an average of 20 persons per day and an approximate total of 1,400 manhours. This paper details the collection efforts, challenges, and lessons learned. It also presents some of the initial findings relating to the debris distribution.

Jan 1, 2019

By Ralph E. Burnham, J. Kelly Ratliff

"The words “dynamite,” “TNT,” “explosives,” and “blasting” typically cause the general public, andjurors, apprehension and fear. Although blasting operations conducted by well-trained, skilled, andexperienced blasters rarely cause damage or injury, the public’s perception of blasting is that it isdangerous, disruptive, and results in damage to nearby properties. As a result, blasting operations have always resulted in complaints, claims, and lawsuits. However, in recent years, the public perception combined with an increase in public opposition, social media, more stringent regulations, predatory plaintiffs’ attorneys, and the application of strict liability to blasting claims has resulted in an increased threat of litigation to blasting companies and individual blasters. Consequently, many blasting companies find themselves receiving more complaints, involved in more litigation, and facing an alarming number of frivolous claims, which can result in increased insurance costs and other financial tolls. Accordingly, today’s blasting companies must be prepared for litigation and take steps to eliminate accidents and claims before the first shot is detonated on a job. The best way to accomplish this is standard operating procedures that incorporate best management practices, industry standards, and regulations in daily operations. This paper outlines some of the considerations that a blasting company should incorporate into its standard operating procedures before, during, and after the shot."

Jan 1, 2016

By Advanced Initiation Systems Inc

10 years in R&D Last 5 years available commercially Worldwide Met strict approvals for manufacturing and use

Jan 1, 2004