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By David Harrison, Edward J. Walter, Meitra Ferek

Agreat tool in the prevention of blasting complaints and subsequent damage claims. In today’s highly competitive industry, we are always looking for ways to become more cost effective. This article investigates the importance of pre-blast surveys-not just for regulatory compliance, but as an overall long term cost cutting and public relations tool.

Jan 1, 1995

By Gabsoo Kim, Rulin Yang, Dave Kay

Blast vibration data, such as PPV are usually scattered. In many cases, plots of PPV versus the charge weight scaled distance are so scattered that useful trends from different blast designs cannot be identified. The scattering of the data may be attributed to the inaccuracy of the PPV measurement, the definition of the scaled distance from a multiple-hole production blast, and the measurement of distances and charge weights. The error from vibration measurements is one of the major contributors to the scattering of the plots. If accurate monitoring is conducted, improved design options may be identified. This paper documents two case examples that compare different vibration sensor couplings. The first case shows mounting accelerometers at spots that protrude from the ground, compared with the sensors that were mounted on a flat ground surface. The second case compares data from loose-sand buried geophone with that from sensors coupled to the ground using concrete blocks.

Jan 1, 2014

By George Harrison

A great many labor leaders and others advocate shot-firers as the acme of relief for all the dangers connected with solid shooting, and where large quantities of powder are used in one blast in coal mines. Legislative bodies in several mining States have enacted laws providing for shot-firers in mines under such circumstances, the blasting to be done at night after the miners have left the mine. With all due respect to the opinions and honesty of purpose of these advocates of shot-firers, it is evident that a great many of them are not considering this important question in the broad sense it deserves and should be considered.

Jan 1, 2008

By Shonn K. McNeill, Joshua Micah Hoffman

Security engineering is similar to other forms of engineering – the design is guided by the loads, materials, and desired function. For facility design, the load is the threat. Facilities that are designed with considerations for explosive hazards are designed with a shot, or series of shots, of a given size and distance from key locations. These facilities range from office buildings and industrial sites in developed nations to military and police stations in contingency areas. The challenge is the design shots are not often communicated to facility owners and managers. If the hazards change, whether it’s due to an increased capacity to cause damage by a threat or a decrease in capacity by a structure, not knowing the design shot means not knowing if security design needs to change. Blast modeling is an engineering tool that can be used to reverse engineer what a facility is suitable for, as well as be a tool for modifying security design for new conditions. This paper will examine military and civilian examples, including a case study of a military facility that did not know their as-built conditions and had to be rapidly closed; due to the determination their security engineering shortcomings could not be mitigated.

Jan 1, 2019

By Bruce Vandenberg, Andy Battfay, Don Lake, Steve Conway, Jeff Yorsz

"High-speed motion pictures are an invaluable resource for blasting analysis. Whether processed by the human eye or a computer, this imagery can provide important insight into a blast and its effects.While certainly popular, traditional high-speed film cameras hamper this process. Instant feedback is not available since film requires developing and, relevant in the case of automated analysis, film isnot immediately compatible with a computer. With these facts in mind, a new high-speed video camera system, the SVCSOO, has been developed. The SVC500 combines the capabilities of a high-speed film camera, the convenience of a solid-state digital video camcorder, and the computing power of a ‘486 PC to provide a complete, standalone platform for high-speed image acquisition and analysis. This paper will describe the design, features, and use of the SVCSOO andcompare these with the analogous aspects of film cameras."

Jan 1, 1994

By Yang Jun, Qu Mei, Zheng Yao-wu, Chi Li-yuan

Due to the necessity of the prediction of blasting seismic effect around strip mine bench blasting area, the paper provides a method to predict the blasting seismic effect by employing the superposition of seed waveform at different monitoring points. The method assumes that blasting vibration waveform per hole is similar to seed waveform at monitoring point. Therefore seismic wave consists of the superposition of the waves from all of blast holes. Firstly, via sensors multiple seed waveforms can be achieved at different distances from signature hole. Then, by using the given dose and the distance, the vibration waveform of a certain blast hole can be calculated by the corresponding seed waveforms. Finally, the initiation delay time interval per hole is added to the propagation time to the predicting point. The predictive waveform at the whole blasting area can be obtained by superimposing all of the single waveforms. Considering the vibration waveform of a single blast hole changes greatly with the distance, under different distances condition the seed wave employed to superimpose is achieved from the similar distance. The experiments demonstrate that based on the method the predictive vibration waveform and spectrum are basically consistent with monitoring results around near-field blast. Compared with single seed wave method, the superposition method of multiple seed wave is more reliable to predict the duration of blasting vibration, the peak particle velocity, dominant frequency and frequency distribution.

Jan 1, 2015

By Stanley Griff, William Herrera, William O. Seals

"The Navy initiated liquid propellant research in the early 1940's. The first promising Navy liquid propellant, Otto Fuel II, was developd in the early 1950 as a potential torpedo fuel. Later, the Navy developed a HAN based liquid propellant designated NOS-365, a hydroxylammonium nitrate, isopropylammonium nitrate and water formulation. A large gas volume generated by this propellant produced a large wake behind the torpedo. As one can readily understand, this negated the useof the propellant for this application. Recognizing the large gas volume as a desirable propulsion system for guns, the Navy embarked upon a gun propellant proqam. Utilizing a bulk loaded gun sysytem, the program failed when the gun was destroyed by the propellant detonating."

Jan 1, 1990

By Timothy Stark

Blasters are usually strictly liable for injury or damage caused by flyrock (trespassory invasion) and blast-induced vibrations (non-trespassory invasion). The application of strict liability to non-trespassory invasions has resulted in significant litigation that has hampered the use of blasting and the blasting industry. Stark (2002) proposes that blasters should not be held strictly liable for non-trespassory invasions but should be liable only if their conduct is proven to be negligent. This change in legal standard was proposed because improvements in blasting technology over the last thirty years allow blasting to be conducted without substantial risk of harm to property and thus the amount of harm imposed by a blast can be related to the level of care exercised by the blaster. It is anticipated that a negligence standard will reduce the amount of litigation because a plaintiff will have a greater burden to overcome. To facilitate the acceptance of a negligence standard by a court of law, this paper summarizes the standard of care using the 1977 Surface Mining Control and Reclamation Act, extensive U.S. Bureau of Mines research, and current blasting techniques, such as blasting mats. It is important for the blasting industry to promulgate a standard of care so a judge can feel confident that blasting can be routinely and systematically controlled and if the legal standard is changed from strict liability to negligence a subsequent judge or jury will be able to evaluate the level of care exercised by the blaster. This paper also suggests that the industry and/or ISEE develop and disseminate a comprehensive standard of care that courts can use to further justify a change from strict liability to negligence and evaluate the standard of care.

Jan 1, 2003

By B. Papilon

Dynamic pressures during blasting can affect performances of both electronic and non-electronic detonators. Boreholes can develop tremendous amount of pressures during blasting. The effect of such elevated pressure especially during electronic delay countdown is probably more acute in electronic detonators. Measuring the pressures during blasting can aid to understand the relationship between magnitude of the pressure developed and the multitude of blasting conditions.

Jan 1, 2013

By Phil Jones, Ben Johnson

During a period of six months in FY2018, a series of trials were conducted to compare drilling accuracy using two different methodologies and the subsequent impact this had on ore dilution. Testing was conducted at Cracow underground gold mine in Queensland, Australia. The drill rig’s existing alignment process was compared to a new technology system with the following observations:

Jan 1, 2019

By Bruce Vandenberg

A 3D, PC based computer program is currently under development by Blasting Analysis International, Inc., to analyze the kinetics of full scale blasts with two or more high-speed motion picture cameras.

Jan 1, 1990

By M. Hagfors

On the underwater testing of explosives, the measuring system consists of water filled test pond, tourmaline based pressure sensor, measuring cable and measuring unit, which supplies the DC current to the pressure sensor. Depending on the length of the measuring cable, it is always possible that some signal damping may occur in case the measurements are carried out without the signal amplifier to keep the measuring system as simple as possible. Therefore the length of the measuring cable should always be as short as possible.

Jan 1, 2006

By Marcello Crispi, Valdir Silva, Juarez Moraes

Companhia Vale do Rio Dote - CVRD is the largest mining company in Brazil and the largest iron ore producer in the world. Serra Geral Mine (SGM) is located at Iron Quadrangle of the State of Minas Gerais, approximately 80 kilometers from Belo Horizonte. Hematite and Itabirite are the two main minerals. A blasting with a spherical charge has been introduced at Serra Geral Mine, an iron ore producer in Brazil, belongs to the CVRD (51%) Kawasaki Steel Corporation (24.5%) others (24.5%), in order to improve fragmentation, as well, load, transportation and crushing productivity. This paper will present the results of a successful blast design with a spherical charge carried out by Serra Geral Mine, the Department of Mining Engineering at Escola de Minas - Federal University of Ouro Preto-UFOP associated to a Blasting Engineering Consultant. The results obtained in the field tests and how it was possible to increase the blast pattern in 53%, which allowed one reduction around 31% in the cost of blasting operation in the Serra Geral Mine, will be discussed in details.

Jan 1, 2002

By Campbell Robertson

The evolution of electronic detonators in commercial mining, construction and demolition has been a transformative journey, characterized by technological innovation, enhanced safety measures and improved precision. This abstract explores the historical progression and key advancements in electronic detonator technology highlighting its impact on the industry as well as the challenges in deploying these types of technologies. Electronic detonators represent a significant departure from traditional initiation systems offering precise timing capabilities and improved reliability and safety. The early development of electronic detonators can be traced back to the late 20th century with the introduction of basic electronic initiation systems. These early iterations provided a glimpse into the potential for greater control and accuracy in blasting operations. As technology progressed, electronic detonators underwent significant refinement incorporating advanced features such as programmable delay times, multiple firing sequences, expanded blast size and enhanced communication capabilities. These advancements revolutionized the way explosives are deployed in mining and demolition applications enabling engineers to tailor blasts to specific geological or environmental conditions and structural requirements. One of the most notable developments in electronic detonator technology is the integration of microprocessor-based control systems. These systems allow for precise calibration of detonation parameters, including timing, sequence, and energy distribution. By leveraging microprocessor technology electronic detonators have become increasingly sophisticated offering unprecedented levels of precision and safety in blasting operations. The advent of wireless communication technologies has further augmented the capabilities of electronic detonators. Wireless detonation systems enable remote initiation and real-time monitoring of blasting operations enhancing safety by reducing the need for personnel in hazardous environments. The evolution of electronic detonators has also been driven by a growing emphasis on sustainability and environmental stewardship. Modern electronic detonation systems are designed, amongst other objectives, to minimize environmental impact, achieve optimal fragmentation outcomes and reduced misfire rates during blasting. These advancements not only improve safety for workers and surrounding communities but also contribute to a more sustainable approach to mining and/or demolition activities. In conclusion, the evolution of electronic detonators has transformed the landscape of commercial mining and demolition offering unprecedented levels of data integration, precision, safety, and environmental responsibility. As technology continues to advance, electronic detonators are poised to play an even greater role in shaping the future of blasting and explosives engineering.

Jan 21, 2025

By John Brennan

OK, I’ll admit it: I’ve always been a big Monty Atwater fan. Not only is the man credited with being the father of modern avalanche forecasting and safety in the United States, but he is also responsible for developing the avalauncher. Through its more than 40-year history, the avalauncher has gone through many changes yet continues to prove its worth in avalanche mitigation work.

Jan 1, 2007

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 A Bagchi, Nabiullah, Jagdieh

"A number of coal mines in India are affected by fire. Most of coking coal reserves in the country are located in Jharia coalfield where more than 18 sq. km is in the grip of fire. Generally such fires are confined in areas near to our crops. About 37 million tonnes of coking coal are lost in recent yearsdue to fire and another 48 million tonnes are blocked in fire areas. Preventive measures adopted to control fires were only partially successful and the cost of such measures was exorbitant I Temperature of blast holes in fire area varies between 60 and 300° C or even more. Even after thorough quenching of holes with water, it become difficult to bring down the temperature below SO"" C. For blasting hot holes primary need is to select safe and suitable commercial explosives and detonating fuse and to measure hot hole temperatures. VWiOUs types of commercially available explosives including Nitro Glycerine bare, slurries, site mixed slurries (SMS), emulsion5 ,detonating fuses and detonators were tested to determine their thermal behaviour at elevated temperatures under field simulated conditions in the Copyright © 2000 International Society of Explosives Engineers 1993g - Studies on Safe Blasting Technique in Fire Area of Coal Mines laboratory and in hot blast holes in field . More than 50 round of blast were conducted in fire areas. NG base compositions and detonators were found unsafe at temperature above SO0 C andtherefore, they are not permitted to be used in hot holes. Slurries and emulsion are stable upto 1200 c. For blasting at temperature exceeding SO0 C a heat resistant gel/ solution was developed by the authors and is being used in number of fire areas."

Jan 1, 1993

By Cristian Rodriguez, Tom BoBo, Maria Rocha, John Kemeny

Blast fragmentation depends on many factors. First of all, it depends on the specific blast design, which includes the amount and type of explosive, the blasting pattern, the timing and sequencing, and other parameters. Secondly, it depends on the properties of the rock mass, including the uniaxial compressive strength (UCS), the rock mass elastic modulus (E), the rock discontinuity characteristics (as reflected in the GSI or RMR), and the rock density. Several fragmentation models have been proposed to predict blast fragmentation based on the blast design and the properties of the rock. These models include the Kuz-Ram model and variations of this model, as well as recent models by Kim and Kemeny (2011) and others. Fragmentation models are validated and calibrated by comparing the predicted fragmentation with actual post-blast fragmentation from image processing monitoring systems.

Jan 1, 2014

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 P. O'Connell, J. Lever, C. Clemence

The Bulyanhulu Mine, Tanzania is constantly trialing ideas for improvements in the drill and blast process. The project work has resulted in a large number of choices in explosive type and charging methods being available for blast design. Interestingly, though booster sensitive bulk emulsion had been introduced to the site to reduce dilution, better results were being obtained from reduced charge columns (decoupled columns of poured anfo in 50mm pvc pipe) and pneumatically loaded anfo upholes, which had been traced. In order to compare the explosive type and charge up-methods, an explosives comparison trial was performed.

Jan 1, 2006