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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 Sean Paterson

The purpose of this paper is to demonstrate a method of delaying and loading a shot. Since entering the construction industry, I have learned that cover is needed on a lot of blasts. When in close having to cover shots was new to me and it seemed time consuming and wastefull. Until I really needed it and didn’t have it. So What To Do??? Remember that safety comes first, if you have concerns cover it. Even if you have to sit on your shot all night to wait for cover. This method is not a replacement for cover, but it will help keep your rock down. Do not bet your life, others lives or your career on it.

Jan 1, 2001

By Erik Nygaard

Ammonium nitrate (AN) is the main ingredient in most industrial explosives, but it is estimated that as much as 80-90% of the global annual production is used as fertilizer [14, 25]. Over the last years AN has been involved in several accidents and used in criminal bomb making. Therefore authorities and legislators worldwide have given it special attention. This paper is divided into three parts: • The first part will focus on the accidents with AN that have occurred over the last years and possible scenarios based on official investigations. • The second part covers safety and security related issues. • The third part will summarize new legislation that is coming both within European Union (EU) and also on a global scale.

Jan 1, 2006

By David Cheung, S. Paul Singh

"The characteristics of a blasted muck pile can have a significant effect on the productivity and economyof loading and hauling operations. Poorly fragmented and tight muck piles, caused by insufficientdisplacement of the broken rock, lead to higher digging and hauling costs. Therefore muck pile must be tailored to suit the loading and hauling equipment. In order to achieve this objective, it is imperative to understand the relevant muck pile characteristics and factors governing them. In general, muck pile characteristics are governed by the blast design parameters, rock mass geology, explosive characteristics and post-blasting requirements."

Jan 1, 2017

By August Ferraz Ribeiro, Guilherme Dias Mendona, Paula Henrique Lisboa, José Silvio Corsini

Correct slope adhesion is related to the conformity of the slope’s real geometry to slope planning. It is very important in mining because slope design has economic and safety implications. Slope design conditions can interfere with mining waste and ore proportion. Without a correct wall, the development of the mine can be hindered, which can reduce the amount of ore available. Furthermore, correct slope design reduces the possibility of melting and allows traffic with equipment and people in the mine. However, defining the wall is a more complex work as the characteristics of the rock require the use of blasting techniques. Therefore, Enaex Mining Technical Solutions (EMTS), in partnership with the engineering team at the Chapada Mine, at Lundin Mining, has developed this study in order to increase slope adhesion. The basis of this study is a near-field vibration test, which enables the creation of vibration attenuation law, and a seed wave damage model has allowed the characterization of the rock present at the Chapada Mine. Then, we could compare the model result to the real slope adhesion achieved with the buffer technique used in the mine. Therefore, it was possible to relate the real result to the model result.

Feb 6, 2023

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 Ewan Selers, Gary Cavanough

Drilling automation technology is well advanced and automated drill rigs are in use at a number of operating mines. This is not the case for the other drill and blast processes due to significant technical challenges to overcome. These challenges, with regard to the current “on bench” practices, include placing the initiators, loading the explosive and connecting up the initiation system. Although difficult, these challenges will be solved with engineering advances.

Jan 1, 2016

By Alastair Torrance

The performance of commercial explosives is clearly influenced by the conditions under which they are used. Mining companies are supplied with Technical Data Sheets which provide details about explosive properties and its suitable application. These are generally produced using laboratory techniques which may not accurately reflect the quality and performance of the product in the field.

Jan 1, 2013

By Edward J. Walter

Our modern technology is provided with a unique but flexible power tool in the use of explosives. A by-product of explosives usage is vibration or elastic deformation of the earth which is annoying to the ordinary person and can be damaging to structures. The problem is not new, it is more than fifty years old. Adequate vibration standards have been developed so that blasting programs can be properly planned and safely executed. Changes in our social culture have somewhat changed the emphasis in blasting vibration from damage considerations to the much lower level of citizen annoyance. Vibration codes based on this level will be highly restrictive and prohibitively costly. Cooperation is urged between operators, community officials, agencies at all levels,and consultants to see to the development of sound realistic vibration codes.

Jan 1, 1975

Over 45 of the Best Qualified Technical Specialists, Consultants, Engineers, Scientists, Explosive Supplies, Educators and Mine Operators in the World!

Jan 1, 2000

By Romel Villanueva L.

"Peru does not produce ammonium nitrate; nevertheless it is a large consumer of both, porous prill (PP) and high-density (HD) varieties. Explosives cost is an important preoccupation in Peru, due tofluctuations of the imported ANFO grade Ammonium Nitrate (AN). The use of Gasified Emulsion (GE)-manufactured with much cheaper HDAN- has become an alternative to reduce such costs. However, some problems were reported in the application of pure GE, including explosive percolation in highly fractured rock and lack of sensitivity by the effect of hydrostatic pressure in very deep holes. It was, hence, proposed to have an explosive based on GE too, but more robust and capable to keep the shape of the explosive column into the blast hole, by minimizing the leakage into the cracks. This could be achieved by adding limited amounts of lower priced HDAN, at the same time of providing gas pressure benefits. Other alternative is to add a low-density material, such as polystyrene prills, into the GE, although it reduces the explosive energy. The chemical gassing controls the density of GE, thus it can be obtained a wide range of densities."

Jan 1, 2016

By C. K. McKenzie

Presents outline of flyrock model and a field procedure to validate predictions of maximum projection distance. Field results are presented from 13 field tests with two different hole diameters.

Feb 1, 2020

By Stewart A. Silling, C. Mick Lownds, Dale S. Preece, Ali Bhuiyan

GEM (Geologic Element Motion) is a Distinct Element Method (DEM) for modeling blast-induced heave. It was developed with a very fast computational algorithm that efficiently treats many different element shapes utilizing alternating arcs and lines to create GEM elements. The GEM computational technique has been previously documented so only a summary will be included in this paper. New features of GEM are the ability to define the size of the rounded corner radius as well the length of the sides for quadrilateral and hexahedral elements. Circles can be created from a quadrilateral element with zero length sides and four arcs. An additional new GEM feature is energy partitioning between brisance and heave. This physics-based partitioning is essential for accurate modeling of blast results over a wide range of rock and explosive types. It accurately defines the volumetric, pressure and energy state of the explosive gases in a blasthole following detonation. Rock mechanical properties and explosive characteristics are included in the calculations. Example simulations provide comparison of the GEM predicted heave for two different classes of explosive. A GEM simulation utilizing hexahedral elements is compared with previous modeling incorporating circular elements.

Feb 6, 2023

By Jorge Cárdenas, Piero Mejía, Diego Gamarra

The present case study details the solution to a complex situation in a mining operation, involving the challenge of expanding the tailings storage facility in high-criticality areas adjacent to electrical rooms that provide continuous power to the entire mining process, including water pumping and drainage systems. For this purpose, blasting is required to prepare the construction areas for the new expansion facilities. Upon deciding to proceed with blasting, a comprehensive engineering assessment was conducted to ensure operational continuity without impacting the process, while generating sufficient fracturing in the rock mass to allow extraction with auxiliary equipment. Support from specialists through the Technical Assistance area was requested, and a detailed evaluation was carried out through advanced studies. Field vibration studies were conducted to define attenuation models and characterize the rock mass in the sector. With this information, simulations were carried out using predictive and probabilistic models with Monte Carlo methods to select delay charges and optimal timing for reducing vibration levels and increasing frequency levels. With these measures, the three blasts conducted near the Gas Insulated Substation room, which had distances ranging from 30 to 100 meters, produced the following results: • Vibrations; The three blasts conducted at distances of 100, 30, and 50 meters recorded vibration values of 5.3, 40.2, and 9.5 mm/s, all of which were below the maximum vibration level of 50 mm/s set by the projects area. According to the USBM RI8507-OSMRE standard, all values for Peak Particle Velocity (PPV) and frequency were below the permissible limits. • Flyrock; Through filming and post-blast inspection, it was confirmed that the ejections were within the safety zone. • Fragmentation; The results obtained showed a maximum overbreak size of 1.5 meters, allowing the broken material to be moved effectively.

Jan 21, 2025

By M. Araos

Non-ideal explosives can be characterised by different methods like velocity of detonation measurement, double pipe tests, underwater tests, aquarium tests, etc., to name a few. Both aquarium and velocity of detonation tests were selected to characterise a non-ideal explosive that is based on hydrogen peroxide, fuel, and void sensitisation. The detonation process in an aquarium of this sensitised explosive was captured at 80,000 frames per second using a high-speed camera. The explosive product was detonated using 51mm (2inches) diameter acrylic pipe charges. The product was detonated at different densities in an aquarium (cube box containing water). An aquarium provides a homogenous confinement for the detonation of explosives and more importantly, allows observing the shock wave as it changes the refraction index of water. The analysis of the video footage allowed the calculation of the velocity of detonation, pressure, gas rate release, and how the shock wave's shape in water changes with densities. It is suggested that the calculation of the rate of gas release could be related to the bubble data obtained from underwater tests.

Jan 1, 2024

By Debra Satkowiak, Ronald Thomas

The Institute of Makers of Explosives (IME), a non-profit safety and security organization founded in 1913, is known for its industry best practices, Safety Library Publications (SLP), some of which have been incorporated into rules by regulatory agencies. The IME developed the first commercial storage, quantity distance (Q/D) table titled “The American Table of Distances” (ATD). It was developed by IME’s legacy association in 1910 and was originally based on observations of structural damage from 117 accidental explosions involving small to very large amounts of explosives, primarily dynamite and black powder. In 1930, the IME published a book, compiled by Ralph Assheton, called the “History of Explosions on Which the American Table of Distances was Based”. The distance in feet in the ATD were founded on the measurements at which inhabited buildings sustained substantial structural damage from the accidental detonation of explosives. For example, minor damage such as window glass breakage and the “shaking down” of plaster was not considered substantial structural damage. Other damage to property that was readily repairable was also not considered “substantial.” It was concluded that unless some integral portion of the building was damaged, the occupants would not be subjected to serious risks.

Jan 1, 2017

By Shadrack Nuamah, Erik Westman, Bright Afum, Jesse Addy

Rock fragmentation is the most critical aspect of hard rock production blasting due to its significant impact on drilling and blasting costs and the economics of subsequent loading, hauling, and crushing operations. This study analyzes current cost trends in the drill and blast operations of an anonymous open pit gold mine and proposes cost-effective drill and blast geometric parameters. The investigation focused on one operational pit with provided design parameters for two shots, shot 1 and shot 2. Existing blast parameters and two additional proposed sets of geometric parameters were evaluated using the Kuz-Ram and Chung and Katsabanis fragmentation models to estimate mean fragment sizes. The results indicated that the proposed blast parameters produced estimated mean fragment sizes within the mine’s desired range (not exceeding 45 cm). Additionally, the explosive energy was utilized efficiently per in-situ material blasted. The proposed parameters increased the estimated total volume of in-situ material fragmented by approximately 14% for both Shot 1 and Shot 2 compared to the current parameters. Furthermore, adopting the proposed blast parameters could lead to significant cost savings. The evaluated total drill and blast cost savings were approximately 11% for Shot 1 and 12% for Shot 2. These savings stem from the increased efficiency and effectiveness of the blast operations, highlighting the potential for substantial economic benefits. This study demonstrates that optimizing blast geometric parameters will allow open-pit mines to achieve desired fragmentation, utilize explosive energy more effectively, and realize considerable cost savings in drill and blast operations.

Jan 21, 2025

By Clay McNail, Paul N. Worsey, John Schillie

"This paper is the result of undergraduate student research over the period of 2 semesters at UMR, which was focussed on developing a practical way to pneumatically stem horizontal boreholes, mostcommonly used underground. The majority of dry horizontal underground boreholes are pneumatically loaded with bulk ANFO. ANFO is preferred due to its low cost and the ease of pneumatic loading. However, stemming underground in the United States is a rare practice. In sharp contrast, stemming material (crushed stone or drill cuttings) is virtually always used in surface holes. The purpose of stemming is to increase blast efficiency by containing the explosive energy in the ground and to reduce environmental effects such as air-blast. The problem with stemming horizontal boreholes are; gravity cannot be used to load stemming material and the ANFO does not have a good interface due to problems with withdrawing the hose and the loading itself. This work follows on from Wilkins’ work on stemming angled boreholes."

Jan 1, 1999

By Scott Stephenson

Making a tunnel through solid rock can sometimes be a dangerous task. Many things must be considered in order to complete such a task safely, and efficiently. Prior to starting things must be known such as, the type of rock, the purpose for the tunnel, the destination point, then angle of decent (or ascent). Once these things are known, the method to proceed must be considered. Factors such as cost, feasibility, and time to completion must be taken into account.

Jan 1, 2009

By Mick Fritz, Gregory Poole

Construction blasting is always challenging when in close proximity to existing structures, but when you are next to a landmark like Sanford Stadium at the University of Georgia it can get intense. Blasting on this project was performed less than 100 feet from students studying in their dorms at Reed Hall. Some shots are only a few feet from the columns on the stadium that hold up the sky boxes where meetings were being held while blasting was being performed. If a shot goes vertical the rocks would go through the floor of the sky boxes.

Jan 1, 2011