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By Elaine Gorham-Bergeron

CAROM is a distinct element, dynamic code developed at Sandia National Laboratories to calculate the motion of rock fragments during blasting.[1] It has recently been improved to incorporate a mechanism for its elements to mimic non-circular rock fragments. With this option, elements stack and move in ways that are characteristic of irregular boulders of blasted rock. In bench geometry, CAROM has been used to examine the possibility of producing variations in muckpile shape due to variations in detonation-time delays between rows. Surprisingly, the shape of the muckpile was predicted to be insensitive to time delays between detonation of rows of explosive, except where the rock fracturing was affected by the time delays.

Jan 1, 1987

BLASPA is the name for a computer code which can assist in the rapid optimisation of blasting procedures in an open-pit mine. BLASPA is based on a mathematical model of the blasting process, a model which has been developing since 1963 as a result of blasting research carried out at the College Militaire Royal de Saint-Jean under sponsorship of the Defence Research Board, and in co-operation with the mining and explosives industry. The model presently includes the following aspects: (1) Geometry, i.e. spacing, burden, bench height, collar, sub-grade drilling; (2) Explosives, i.e. types and grades of explosives, distribution into bottom and top load or decking, size of hole and coupling; (3) Hookup, i.e. parallel or angled firing, delays, location of primers. Computer costs are very small, by comparison with purely spherical AEC codes, so that any number of simulations can be carried out very efficiently. The system has already been used to carry out thousands of simulations for over 40 mines in Canada and abroad. It will be explained how such simulations become a useful guide for a mine's blasting engineer who wishes to optimize his blasting and drilling costs.

Jan 1, 1980

By Sam Taoum, Omar Riahi

Few tools allow for accurately tracking ore dilution after blasting. Existing methods often rely on data analysis or linear interpolation of velocity, which can be imprecise and less effective in varied geological settings. A promising alternative is the use of numerical simulations, which involve complex mathematical calculations incorporating real physical data about explosives and geological characteristics. These simulations can model blast-induced fragmentation and subsequent ore dilution with greater accuracy, providing detailed insights into blast dynamics by considering factors such as explosive type, blast pattern, and rock properties. Numerical simulations integrate data from sources like seismic sensors, blast monitoring equipment, and geological surveys, offering a holistic view that single-method approaches cannot match. By simulating different scenarios, mines can predict the outcomes of various blasting strategies, optimize blast designs to minimize ore dilution, and maximize recovery. Advanced numerical simulations enhance the prediction of fragmentation distribution and size post-blast, crucial for effective dilution control and maximizing ore recovery rates.

Jan 21, 2025

By Zhiwei Jiao, Ziqing Guo, Mushen Wang, Yueda Fang, Qiuming Tang

In order to achieve anti-terrorism, production safety, better explosive performance, lower cost, and environment protection, we developed HMS (emulsification in borehole).Long-process PM (plant-mixed) and SM (site-mixed) emulsion trucks are reviewed and compared to a new type of short-process HM (hole-mixed) truck for onsite emulsion manufacturing. The short-process HM truck has demonstrated many advantages over its PM and SM counterparts in areas such as process safety and security, energy efficiency and environmental impacts: 1) No emulsion matrix is manufactured in the plant, transported on public roads, or even present on the surfaces of blasting job sites. Such characteristics are certainly beneficial in eliminating risks of the product being diverted and used by unlawful players; 2) This short-process involves "micro-fluid control to form super oil phase-rich" in tubular emulsification process, making it intrinsically safe; 3) There is basically no residual matrix left in the truck or on the job site to clean up, which greatly reduces environmental impact of the process; 4) Comparing with typical PM and SM trucks, the HM truck has eliminated the needs of many power equipment and critical pump pressure for turbulent flow forming a static emulsification with super oil phase -rich is only 0.2Mpa. These is therefore quite energy efficient.

Feb 1, 2020

By Rene A. "Moose" Morin, Craig Copping

Innovative concepts in drilling and blast design have been used to remove deteriorated concrete and have enabled contractors to reduce costs and time on St. Lawrence Seaway rehabilitation projects. Time is of the essence on these contracts since the Seaway system is only available for this work during the winter freeze up. Unique electrical sequential initiation systems and specially modified drilling equipment have been used to accurately remove a narrow slice from the 83 foot high lock walls. These new methods successfully reduced demolition time, minimized overbreak and adhered to strict vibration limits.

Jan 1, 1986

By Robert L. Martin, Brian W. Stump

"The Black Thunder Mine is located in the Powder River Basin of Northeastern Wyoming. Over 39.2million tons of coal were produced at the Black Thunder Mine in 1996. Just over 100 million pounds ofANFO/Emulsion blend were consumed in that same year. Currently around 30% of the overburden is cast to final with the use of explosives. With plans for a mine expansion, explosives will continue to play a very vital roll well into the future."

Jan 1, 1997

By P Albert

A wedge-shaped underwater rock plug has to be blasted in order to tap the reservoir and furnish water to a new underground powerhouse at Manicouagan-5. The paper deals with the design and engineering aspects of drilling and blasting of this plug where the topographical configuration is extremely difficult. In this study small diameter vertical holes are considered with the OD-method and a fixed platform is recommended for drilling and loading operations.

Jan 1, 1984

By Ettore Contestabile, Cameron Thomas

Implosive-type electrical/mechanical connectors such as XECONEX have been used extensively for joining electrical transmission lines. This implosive action of explosives has also been applied to other forms of high energy metal working with excellent results. However, as with many other products, the inherent blast energy of these units has caused some environmental concerns especially when used in proximity to inhabited areas.

Jan 1, 1995

By Alday B. Andrews

A computer program called Seiswise that predicts the character and intensity of ground vibration generated by surface blasting operations was developed and field tested. The program uses the time histories of one or more pilot shots in combination with various initiation sequences to construct synthetic seismograms which are examined to select designs that will produce low levels of ground vibration.

Jan 1, 1990

By Y Omura

If dynamite is used in hot metal mines, it may be subject to decomposition, and the increase in nitroglycol vapour under the high temperatures causes bad headaches of workers. Also the explosives containing ammonium nitrate are very dangerous when mixed with sulfide ores at a high temperature!. Therefore we developed a heat-resistant water gel explosive which is safe to be handled at these hot metal mines.

Jan 1, 1983

By Tim A. Beattie, John R. Grant, David L. Kennedy

After many years of research, ICI staff have developed a numerical modelling system for the study of detonator/primer/explosive configurations. Results from this work clearly identified that current primer designs were not as effective in delivering their energy potential as needed. Alternative designs were evaluated and several prototypes, all essentially spherical in shape, were built for testing. Results have shown a significant improvement in various aspects of primer performance, including omni-directional pressure transferral and increased energy release rates. Reliable, high performance priming of explosives is now achievable for a much wider application range.

Jan 1, 1991

By T Davids, O J. Jordaan, M D. J Bonneau

As in most other parts of the world, the surface coal mining industry in South Africa is introducing emulsion explosives as the primary bulk blasting agent for use in wet borehole conditions where AN/FO cannot be used. Most of the emulsion products presently in use are gassed to provide sensitivity. The intimate mix between the fuel and oxidizer in the emulsion has been shown to produce a highly efficient explosive. However, a major difference between emulsion and the previous slurry products is its relatively low physical strength. This prompted Rand Mines' Duvha Opencast Mine, a major South African Escom power colliery, to conduct test work to illustrate the effect of emulsion physical consistency on blasthole loading. This paper presents the results of test work conducted at Duvha to investigate the problems associated with loading both AN/FO and emulsion in water filled holes, stemming emulsion holes, and in particular, to illustrate the difficulty in correctly introducing a stemming deck into the emulsion column. Time dependent behavior of the loaded emulsion holes is investigated. Velocity of detonation measurements for freshly manufactured emulsion, and for emulsion after loading through water with sleep times of up to 10 days, are presented.

Jan 1, 1987

By Roger Keller, Jason Ryan

A number of studies have evaluated excavation methods for the construction of subsurface facilities for a potential deep geologic repository for the disposal of nuclear waste at Yucca Mountain, NV. Many of these studies suggest that where TBM (tunnel boring machine) methods are not applicable and alternative mechanical excavation methods can not efficiently excavate harder rock drill and blast methods may be the most efficient means of excavation. However, a number of concerns regarding drill and blast applications have been raised in these evaluations, most notably the affects of blasting on the surrounding perimeter, as isolation of the waste by the natural barrier of the surrounding rock is a key element in the concept of a deep geologic repository.

Jan 1, 2001

When CIL presented their new theory of the Breakage Process and Delay Blasting at the 74th Annual Meeting of the CIM in 1972(1), there was hardly any open pit operation in Canada that was using longer than 25 msec. delays. To the contrary, 10 and 15 msec. surface relays were common, which in our opinion were no delays at all for open pit blasting.

Jan 1, 1979

By Roger N. Prescott

This report presents a new process in delay blasting with the use of ANFO and slurry explosives.

Jan 1, 1977

By M. L. Mendes, J. Q. Nojiri, S. C. Botelho, A. P. Campanha

In February 28, 2001 JOULE coordinated the first tests with an electronic detonator in South America at an iron ore operation - ITABIRA MINES from the Brazilian COMPANHIA VALE DO RIO DOCE (CVRD) - the largest producer and exporter of iron ore in the world. ITABIRA MINES (CAU and CONCEI O) belong to one of the complexes, called the Southern System, producing 56 million tons of ROM as well as concentrated products and pellets. This paper is going to describe the tests at ITABIRA MINES with results indicating the improvement in the excavator productivity and reduction of the mining global costs (due to the better performance of the equipment and potential reduction of the maintenance cost).

Jan 1, 2002

By A Lance McAnuff, Robert T. Booren

Construction of a dock facility for the Lake Erie Development Project of Stelco Steel involved underwater blasting in commercial fishing waters near Port Dover, Ontario. The most stringent environmental constraints were imposed and a monitoring program involving water overpressure recordings, using equipment developed specifically for this assignment, correlated with observation of caged fish specimens at various distances from the blast source, was undertaken to determine the effects on fish life and to establish whether a protective air-bubble curtain system should be installed around each blast area.

Jan 1, 1989

By Phillip R. Mulligan, Catherine Johnson, Edward Kinzel, Cody Lough, Jason Ho

A shaped charge is an explosive device used to focus detonation energy in a desired direction. Shaped charges have numerous applications in several industries such as oil extraction, weaponry and demolition. The focusing of the detonation energy is the result of the Munroe Effect, which greatly increases the penetration properties of the explosive due to a void in the explosive’s volume. The void in the explosive is lined with a metal substrate that becomes a super-heated projectile when the explosive is detonated. Additive Manufacturing (AM) can allow greater design freedom and geometric complexity for the liner portion of the shaped charge. Specifically, hierarchical structuring and functional grading can potentially provide greater velocity, directionality, and efficiency. By utilizing AM, the conventional use of shaped charges can be greatly expanded upon and may open new possibilities. In this work, selective laser melting (SLM) was used to explore different conical shaped charge (CSC) liners made out of stainless steel 304L. A series of liners were tested that had varying densities and were compared to conventional liners. The CSCs were filled with the high explosive Composition C-4 and detonated to evaluate performance. The blast events were recorded using break wire screens to calculate the velocity of the jet through steel target plates over a standoff of 6 times the charge diameter. A high-speed camera recorded the blast event to calculate the velocity of the jet through the air. The depth of penetration into the steel target plates was also used as a measurement of the effectiveness of the CSCs. The aim of this work is to show the potential for advanced shaped charges produced using SLM.

Jan 1, 2019

By Emily Johnson, Catherine Johnson, Ben Sonpon, Kelly Williams

The effect of length to diameter of the detonator is compared using Ansys/Autodyn 2-D simulations, the results of which are validated experimentally. It was found that higher pressure comes with a larger diameter, because it will result in more explosive energy being allocated out the end of the detonator.

Feb 1, 2020

By L. Chaves

In rock blasting, due to numerous factors, both controllable and uncontrollable, the execution rarely meets the planning. The powder factor is an important KPI for blasting since it represents the amount of explosive used to fragment the rock, therefore it depends on the rock mass characteristics and may be influenced by factors such as weathering and drilling quality. The blasts at the Serra Sul mine, S11D project, are usually big blasts and the high productivity is a challenge for maintaining the quality of the whole drill and blast process. It is important to know the contributions of each of the most common influencing factors of the powder factor to direct the efforts to the improvement of the process. A buildup model is presented to evaluate the contributions of five influencing factors to evaluate the planed x executed powder factor. The factors considered in the model are the average hole depth, the amount of hole/blasted volume, the stemming and decking length, the linear charge weight, and the density of the explosive used. The build-up may be applied for both individual blasts and for overall view of the blasts in a period. A case study is presented with the application of the model for the monthly powder factor analysis at Serra Sul mine has contributed to direct efforts to enhance drilling quality and preservation of the drilled holes.

Jan 1, 2024