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By Kia Riihioja, Mike Higgins

A major difference between electronic and pyrotechnic detonators is that, in almost all but the simplest of blast layouts, computer software is required to plan a blast using electronic detonators. While it may be possible to program delay times without software, using only the manufacturer’s control hardware, the full potential of electronic detonators can only be realized through software. Until recently, the only software available has been provided by the suppliers of the electronic detonators. These usually have just enough features to create a hole layout and to assign times to the detonators in the holes. The software is also able to communicate only with the manufacturer’s detonators. This means that the client may be compelled to change several parts of the blasting process when a different delay system is adopted, from design through to implementation and reporting, even though these may be sub-optimal at the client’s mine. While many authors have demonstrated improvements in blasting outcomes using electronic detonators, very few have discussed how the delay times were calculated. Where the calculations are discussed, it is also obvious that the delay times must be monitored and re-evaluated as conditions in the mine change. For example, the principles of superposition and scaled distance, burden relief and energy cooperation between holes should be checked constantly for different locations within the mine, changes in rock properties, or even for differences between design and actual hole positions. The most common methods in blast design software to calculate delay times are inter-hole interval, relief contour and direct editing. Although they are simple in concept, they can result in fundamental errors if they are not applied correctly. The software for electronic blast designs should be capable of not just a timing calculation, but also of showing, to some degree, the impact and interaction of the calculated times.

Jan 1, 2004

By Stewart A. Silling, D. Lynn Gordon, C. Mick Lownds, Dale S. Preece, Ali Bhuiyan, Patrick R. Bowden

Blast heave modeling and prediction utilizing the new discrete element model, GEM, that treats rock as elements with alternating arcs and line. Explosive loading of GEM elements is accomplished by utilizing the Noble-Abel equation of state to track the gas pressure from detonation through expansion to atmospheric pressure.

Feb 1, 2020

By Steve Linehan, John Toedter, Kelly Williams, Mark Herman, Laura Connor, Catherine E. Johnson

Minimum safe distance (MSD) calculations are used widely in military applications to determine safe standoff distances for breaching personnel. Accurate safe distances and an understanding of blast wave propagation are critical to preventing traumatic brain injury. These calculations are often based on spherical charges in open air. However, applications including explosive breaching use planar charges rather than spherical. Previous studies analyzed the shock propagation of a square planar charge of sheet explosive and concluded the anisotropic pattern conflicted with the Kingery Bulmash (KB) and MSD spherical models. It has been determined that these predictions do not adequately predict the realistic pressures in all directions and the trend has shown to be consistent across multiple charge geometries. In this series of experiments, pressures were collected from reference spheres and rectangular geometries of detonating cord and sheet explosive commonly used in breaching and improvised demolition for this comparison. This common configuration showed pressure differences at varying angles to the charge with the highest pressures measured at the 90° position perpendicular to the “door” to be breached. Lower pressures were found at the 0° and 15° positions where the breachers would normally be standing. The reflected shock from a surface such as a door was incorporated in a semi-confined situation and added to the shock observed by the breachers. Urban environments include many surrounding structures for these reflections to occur and further testing is necessary in such an environment to determine the full-scale impact. These findings may be useful to develop improved MSD calculations for breaching applications based on charge geometry, orientation to the blast, and nearby structures.

Feb 6, 2023

By DuPont Magazine

RBH Note: as stated many times in these articles, frozen dynamite was one of the greatest hazards facing the blaster. It wasn’t until the late 1920s that it was solved for good, with the introduction of nitrated ethylene glycol as a partial replacement for nitroglycerin in dynamites. The du Pont low freezing dynamites contained TNT, DNT, or nitro-substitution compounds of various sorts.

Jan 1, 2015

By Luana Ferreira de Carvalho, Aurelio Manço Garcia, Gustavo Sampaio Lopes, Jose Silvio Corsini, Davi Bastos Martins de Oliveira

The Enaex Mining Technical Solutions (EMTS) team, in partnership with the Anglo American Iron Ore Brazil drilling and blasting team, has developed a study aiming to optimize the blast design applied at the Minas-Rio project. The study consists of modeling the dynamic behavior of one lithological domain to determine the best configuration of drilling pattern, charge configuration, timing and sequencing of the blast designs applied at the mine in this particular rock. The first stage of the study was the recognition of the rock blast process in question, assessing key parameters that characterize this whole operation: geomechanical characteristics of the rock mass, implementation quality for drilling pattern and explosives charging (collar position, hole depth, explosive charge length and stemming size) and recognition of current blast designs. The central element of this study was the creation of a vibration attenuation and seed wave model which has allowed the characterization of this particular rock mass present in a region determined by the Minas-Rio team. The model is based on a near field vibration test, constituting a powerful tool in the design of blast parameters. The blast design developed from the damage model simulations basically modified the timing and sequencing. The aim of this study was to improve the fragmentation resulted by the blasting, considering the particle size requirements demanded by the primary crusher and to increase the productivity of the loading and hauling operations. The results were analyzed considering the effective productivity of the two different fleet types of shovels, where the authors have analyzed more than 46000 values of productivity from September 2017 to August 2018, taken from the Dispatch system. A significant increase in effective productivity of these load equipment was observed, 7% to the PC4000 fleet and 2% to the PC5500 fleet, values supported by statistical parameters and hypothesis tests.

By Ian Bell, Saman Nouranian, Shahram Tafazoli, Bahram Sameti, Mahdi Ramezani

"Image-based rock fragmentation sensing in mining and quarry applications includes an important rock boundary delineation step, which is commonly referred to as rock segmentation. This paper presents a novel approach to solve this problem, using artificial intelligence. In the proposed technique, priorknowledge of previously analyzed images is encoded into mathematical/statistical models. A set of human labeled images are used as training inputs. These images are used to train neural networksthrough an optimization process. The networks can then be used in real time for rock delineation. "

Jan 1, 2017

By Svatopluk Zeman, Zbynek Akstein, Jiri Pachman, Ahmed Elbeih, Marcela Jungova

BCHMX (cis-1,3,4,6-tetranitro-octahydroimidazo-[4,5-d]imidazole or Bicyclo-HMX) was studied as an energetic component of three different plastic explosives based on three matrices: C4 matrix, semtex10 matrix and silicone matrix. The original plastic explosives, Composition C4 - based on RDX (1,3,5-trinitro-1,3,5-triazinane), Semtex 10 explosive based on PETN (pentaerythritoltetranitrate) and plastic RDX-silicone, were included for comparison. Sensitivity and performance parameters were studied.

Jan 1, 2011

By Alan Hooper, James E. Mischler

Construction began in 1984 for a 5 megawatt hydroelectric power retrofit at the O'Shaughnessy Dam for the City of Columbus, Ohio. The construction necessitated excavation of limestone bedrock up to 27 feet below the normal water level of the river downstream of the dam. Proximity to the river and difficult terrain resulted in an interesting and challenging construction project.

Jan 1, 1986

By Adrian Moore, Alan Richards

"It has been common practice to set blast vibration limits for structures using an “observational”approach whereby limits are set at a level based on observations of damage, or the lack ofdamage, combined with a tendency to further reduce the permitted level due to uncertainty. Suchan observational approach was used in the USBM RI 8507 to produce the frequency dependent‘Safe Levels of Blasting Vibration for Houses’ which has become a universal Standard for overthirty years."

Jan 1, 2013

By Kristen R. Bingham

"Today, more than ever, drilling and blasting contractors are challenged to manage the ever-changing risks associated with blasting operations. New neighborhoods are encroaching upon mine sites and blasting projects are confronted with increasing scrutiny by permit issuing authorities and nearby residents disgruntled by new construction. The act of transporting explosives material to and from thejobsite is far from easy and trouble-free. At the same time, the pressure to stay in compliance with the growing number of government regulations continues to mount. While new tools and technology are appearing in the workplace to address some of these challenges, losses still occur. Can the datagenerated by this technology help drilling and blasting contractors make better decisions? While basic risk management principles are still applicable, do new tools and technology assist in the effort to prevent losses? What are the downsides? In this age of new technology, is face-to-face interaction still necessary? While technology is certainly a useful component in the drilling and blasting world, can it be helpful in defending claims?"

Jan 1, 2017

By Luana Ferreira de Carvalho, Aurelio Manço Garcia, Gustavo Sampaio Lopes, Jose Silvio Corsini, Davi Bastos Martins de Oliveira

The Enaex Mining Technical Solutions (EMTS) team, in partnership with the Anglo American Iron Ore Brazil drilling and blasting team, has developed a study aiming to optimize the blast design applied at the Minas-Rio project. The study consists of modeling the dynamic behavior of one lithological domain to determine the best configuration of drilling pattern, charge configuration, timing and sequencing of the blast designs applied at the mine in this particular rock.

Feb 1, 2020

By Paul Worsey, Yasutaka Dote

The choreography of large fireworks displays dictates electric initiation for precise timing. It has been common practice to pre-squib products before transportation for reducing set up time. A number of fatal accidents transferring pre-squibbed product during transportation suggests that there is a problem with impact sensitivity. The aim of this paper is to quantify the impact sensitivity of the various configurations of initiating materials used in display fireworks.

Jan 1, 2009

By M. Szumny, P. Mertuszka, K. Fuławka

Mining-induced seismicity is one of the adverse side effects of mining with the use of explosives at great depths. Disturbance of the primary stress state by the development of the network of excavations combined with the continuous generation of dynamic loads by the detonation of explosives in mining faces has a negative impact on the level of safety of crew and machines. To ensure the stability of excavations it is necessary to identify in detail the nature of the seismic hazard by means of continuous seismic measurements. Unfortunately, the technologies used so far are characterized by high costs of installation and further maintenance, which clearly limits the possibility of using a large number of stations in a small area. A breakthrough in this matter may be the technology of microelectromechanical systems, which is several times cheaper than standard solutions used in mining seismology. This technology, with the appropriate configuration of devices, can be successfully used to monitor dynamic phenomena generated by mining activities. As part of this study, the assumptions and configurations of a prototype 42-channel accelerometer network using MEMS technology have been presented. The network was installed in the Lubin underground copper mine in Poland in a seismically active area, where multi-face destress blasting are conducted regularly. As a result, 14 tri-axial accelerometers were installed in the immediate vicinity of the active mining front at a distance of about 1,000–4,000 ft (300–1,200 meters) from the closest faces. Highfrequency recordings are collected based on algorithms that trigger the system when the Peak Particle Acceleration set value is exceeded or on the basis of a manual external triggering device connected to the blasting machine. During the measurement period, several high-energy seismic tremors and several dozen of waveforms generated by blasting were recorded. The obtained results are the basis for assessing the effectiveness of the destressing measures and for the analysis of geomechanical risk based on periodic analysis of the velocity of seismic wave propagation

Jan 1, 2024

By John Tatom, Michelle Crull, Robert Conway

The US Department of Defense Explosives Safety Board is sponsoring the development of a risk-based explosives safety siting program, SAFER. The fragment and debris hazard generated at the potential explosion site (PES) is critical at an exposed site (ES) over a significant range of standoff distances. The Science Panel Impact Debris Evaluation and Review (SPIDER) test program has been planned to develop improved predictions for the hazards inside an ES by fragments and debris. Data will include the mass and velocity required for perforation of the test cross-section and the characteristics of all debris produced inside the ES.

Jan 1, 2010

By D. S. Preece, S. Silling, A. Bhuiyan, C. M. Lownds

GEM (Geologic Element Motion) is a Discrete Element Method (DEM) capability for blast-induced heave simulation with a very fast computational algorithm that can efficiently treat many different element shapes by utilizing alternating arcs and lines. GEM calculates rock motion from a knowledge of the gas pressure moving the elements. This requires an expression for the pressure vs volume, or the adiabat, of the explosion product gases. This work uses an analytical expression for the adiabat derived from the explosive’s properties. The effect of the explosive detonation pressure in crushing an annulus of rock, and setting up a shock wave, is termed Brisance. GEM incorporates a working hypothesis for the deleterious effect of Brisance on subsequent rock motion.

Jan 1, 2024

By Charles R. Barnhart

The Nitrogen Dioxide Cloud: After one year of testing it can be stated that we do know and understand a great deal about why the nitrogen dioxide formation is exacerbated in cast blasting. Picture 1 is an example of how concentrated the NOx can be from a cast blast. It has long been felt that 300 or more milliseconds of timing needs to be put between each row of detonations to allow the rock a maximum time of flight so the cast percentage is high. Our experiments have found that higher cast percentages can make with timing between 150 to 200 milliseconds between rows. Picture 2 show a definite improvement in nitrogen dioxide concentration and most of that was the result of shooting a previously shot end of the cast pattern that had not been dug, thus no confinement of the powder columns.

Jan 1, 2004

By Tyler Rockley, J. P. Remi Proulx, Ruilin Yang

A highwall blast vibration project was carried out to quantify the level of blast vibrations produced from a trim blast in soft rock and a combined production and trim blast in hard rock. Combining production and trim blasts could be performed without exceeding the mine’s vibration limits.

Feb 1, 2020

By NA NA

Copyright © 2020 International Society of Explosives Engineers

Feb 1, 2020

By Galetakis M., Deligiorgis B., Xiroudakis G.

Fragmentation prediction is important in surface mining to optimize downstream processes such as loading, hauling, comminution, and beneficiation processes. Traditional approaches, such as the Kuz-Ram model, image-based fragmentation analysis, and numerical simulations, rely heavily on large datasets acquired after blasting. Moreover, due to the inherent limitations in each method there is an underestimation of fine and coarse fragment sizes, when applying these models without prior knowledge regarding the fragmentation distribution. These drawbacks are restricting their use only in post-blast parameter prediction. In response to these inefficiencies, this study presents a deterministic fragmentation prediction methodology based on a single-blasthole model. The model simulates the formation of the damage zones around a blast hole based on the number of cracks within a distance from the centre of the blast-hole and correlates them with an estimated fragment size in each domain. A fragmentation distribution from the literature is employed to validate the proposed approach and the results are compared with those generated using a modified Kuznetsov model. This approach aims to enhance blast design decisions by enabling pre-blast fragmentation prediction. Based on this, blast designs could be estimated depending on the desired fragmentation before blasting, giving the opportunity for a tailored to local rock properties optimization.

Jan 26, 2026

By TTE-Europe GmbH

A few years ago, the term Track & Trace for explosives was only known in Europe and Brazil at most; the introduction of this technology is experiencing an undreamt-of boom worldwide. More and more countries are enacting legislation to introduce Track & Trace of explosives and follow Europe and Brazil on this path. At present, the world's leading manufacturers are already using such solutions, are in the process of implementing them, or are in the planning process. However, based on the experience gained in Europe, there are outstanding challenges for all manufacturers. These are questions of compliance, logistics, distribution, and, of course, especially, the necessary adaptation of the production environment. However, this development involves considerable effort on the part of the manufacturers. New devices for marking the explosives and digitally recording the data are integrated into the production process. This should be done as cost-effectively as possible, without restricting production capacity and speed, and with as few process changes as possible. This paper uses real-life customer experiences examples to explain paths from project design to real implementation. Lessons learned from the experience of European explosives manufacturers are presented, missteps are described, and solutions are identified. Individual steps along this path are explained, and solutions are told to avoid pitfalls and bottlenecks. Finally, it refers to the risk analysis and concrete examples in implementing the planning into production. Methods of marking various explosives are shown, and the use of Track & Trace to solve logistics tasks in picking and shipping explosives, including the data exchange with ERP (Enterprise Resource Planning) systems.

Jan 26, 2026