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By Jeffery L. Dean

Founded in 1974, the ISEE has grown to more than 3600 members representing 72 countries. The Society and its 35 chapters in the US, Canada and Australia promote research and education, provide forums for the exchange of explosives technology, serve as a repository of explosives information, provide expert help to governments, conduct certificate/training programs, and promote the teaching of the safe and controlled use of explosives.

Jan 1, 1997

By Brian W. Stump

"Seismic waves from explosions can be used to characterize physical processes in and around the source. The quantification of absolute levels of ground motion is important for minimizing impact on nearby people and structures. We contrast work in characterizing seismic radiation from contained nuclear explosions with ground motions from multiple explosion quarry blasts. A physical basedunderstanding of the explosion source function allows prediction and extrapolation to new environments where experimental data may not exist."

Jan 1, 1990

By S. K. Chan, C. Badeen, S. Goldthorp, H. Feng, I. Alilovic, R. Turcotte

Over the last few decades, water-based explosives and their precursors, despite their apparent insensitivity, have been involved in a number of accidents around the world. A large proportion of these accidents occurred when these emulsions were pumped either for their manufacture, transport, or handling. In Canada, this has led to the development of “Guidelines for the Pumping of Water-Based Explosive”, which state that “using pumping pressures well below the laboratory measured minimum burning pressure (MBP) of the corresponding emulsions or watergels is a good safety practice”. However, in the above document, there is no description on how the MBP should be measured. In the last few years, a research program at the Canadian Explosives Research Laboratory (CERL) in collaboration with Orica has been focused on the development of a validated measurement protocol for realistic MBP measurements.

Jan 1, 2014

By Wang Hong Qu

This paper observes the shape of throw explosion crater its ejecta locus of internal medium and the process of distance along with slope's angle developing. It was discovered that initial velocity is inversely proportional to slope's angle. The velocity of surface distribution at the lower half crater of explosion is larger than at upper one. It carries the relevant calculated formula and physical process of explosion crater forming under the inclined boundary conditions, and some important law. It proved that the gravity influence is very distinct for the blast action in the little resistance line.

Jan 1, 1991

By Junya Tokita

In Japan, packaged explosives have traditionally been used as the most common explosive for tunneling. Recently, some blasting systems such as ANFO with a kettle loader and emulsion explosives with a pump loader have been trialed in order to improve safety and efficiency of the charging process. There are issues with these systems relative to the Japanese market. ANFO dissolves in water easily, and generates ammonia gas when it contacts with concrete. Emulsion explosives need costly pump ing unit s, and there is a need to control residuals in the pump unit. Additionally, there are obstacles by Japanese law to site mixing of emulsion explosives.

Jan 1, 2005

By Randall M. Wheeler, Kenneth K. Eltschlager

Blasting Seismographs use microphones to measure air overpressure from blasting. The microphone height above the ground has been the object of some controversy. The current ISEE “Field Practice Guidelines for Blasting Seismographs” specify microphone placement within 1.2 inches of the ground or over 3 feet above the ground. In this study, air overpressure measurements were taken at different height intervals and compared. Blasting seismographs constructed to the ISEE “Performance Standards for Blasting Seismographs” were used to monitor construction, quarry, and coal mine blasting. Near and far field measurements were taken to obtain representative spectral and amplitude ranges. The comparative analysis shows that microphone height has negligible impact on air overpressure measurements.1

Jan 1, 2005

By James L. Austing, Allen J. Tulis, Ronald Pape, Ronald G. Draftz

In a certain sense, the explosives industry began in the 13th century with the invention of black powder, which is an intimate mixture of sulfur, carbon black or charcoal, and potassium or sodium nitrate. For several centuries thereafter, black powder was the sole general purpose energetic material, serving as an igniter, propelling charge, bursting charge, and blasting agent. By today’s standards, black powder is totally inadequate for the latter three functions, but its use continues as an igniter for propellant charges because of its unique ability to ignite and burn under ambient conditions. The history of the development of black powder was reviewed by Rose (1980).

Jan 1, 1995

By David Reddick

The mining industry is in the midst of dramatic change. Mining activities are moving from industrialized first world countries (Canada, Australia, and the United States) to the third world. This shift is occurring due to depleted reserves, tough environmental standards, and expensive labor in traditional mining countries. During a recent trip to South Africa, I was asked, owing to my educational background in economics and an international involvement in drilling and blasting, what changes could be anticipated in third world blasting practices as labor costs increase. It is from that beginning that this presentation has evolved.

Jan 1, 1997

By Don W. Lake

Of all the blast monitor& instrumentation systems and techniques av&able today, highspeed photography and videography remain as the most valuable, stand alone, diagnostic techniques to evaluate full scale blasts in the mining and explosives industries. Highspeed image data, coupled with information from other instrumentation systems, such as continuous VOD records, seismographs, laser surveying systems, refraction seismographs, etc. can eIiminate many assumptions about what actually took place in a blast. Thus, diagnostic confidence in evaluating both good and bad blasts is increased, and optimum blast designs are achieved considerably faster when compared to the trial and error approach or relying on just the experience factor.

Jan 1, 1992

By Dale S. Preece, J Paul Tidman, Stephen H. Chung

"A discrete element computer program named DMC-BLAST (Distinct Motion code) has been under. development since 1987 for modeling rock blasting (Preece & Taylor, 1989). This program employsexplicit time integration and uses spherical or cylindrical elements that are represented as circles in2-D. DMC-BLAST calculations compare favorably with data from actual bench blasts (Preece et al,1993)."

Jan 1, 1997

By Don Novotny, Dana Spencer

In this workshop our intent is quite simple; that is that we will introduce a relatively new technology that may have applications in blasting applications. This technology is the laser initiation of explosives. This workshop course is not intended to suggest ways in which specific blasting problems can be resolved. That is the purview of experts within each of your fields.

Jan 1, 1994

By Italo Onederra, Jason Furtney, Ewan Sellers

The detonation reactions occurring during rock blasting result in high pressure gas phase products from the condensed explosives typically used in mining applications. After detonation and the initial fracturing, the work done by the expansion of this gas contributes to burden movement and further rock fracturing. Before all of the energy in the reaction product can do useful work on the rock, some of this energy is lost to crushing and possibly to gas venting to the atmosphere. Borehole gas pressure decreases by three principle mechanisms: (i) expansion of the borehole cavity, (ii) flow into the fracture network, and (iii) flow through the stemming. To simplify the problem and to get a better understanding of the interaction of these mechanisms, a simple model for each of these mechanisms is developed. A comparison is made of the time-scales and the influence on burden movement for each. A comparison of gas flow behavior is made between typical ANFO and emulsion products.

Jan 1, 2012

The common approach of designing blasts on a trial and error basis is quickly coming to an end. When utilizing the full scale blast environment, trial and error can quickly become cost prohibitive and leaves much to be desired in terms of true blast diagnostics. In these situations testing is usually only continued until a perceived improvement is achieved and when the gross undesirables in blast results are removed. This does does not preclude, however, that further improvements of up to 100% or more can not be obtained.

Jan 1, 1991

By Tony A. Rorke, Joe R. Brinkmann

The application of instrumentation to better understand and improve production blasting is one of the most fruitful areas of explosives and blasting research. The majority of instrumented studies of production blasting have relied on the extrapolation of far field measurements to postulate blast performance in regions of interest closer to the charge where rock breaking takes place. However, the nonlinear and dissipative nature of the quantities being measured raises serious questions as to the accuracy and validity of such extrapolations.

Jan 1, 1991

By Yoshikazu Hirosaki

How big or small is the Japanese explosive market? Who are the major explosive customers? Is there any big construction project in which a large amount of explosives is expected? What is the future of the explosives industry in Japan? Is it true that there are no ANFO trucks? What is the licensing system for blasters? Is there any education system for blasters?

Jan 1, 2001

By Rennie Kaunda, David Streeter, John Kemeny

This paper describes a field/laboratory study that was conducted in cooperation with a mine in Arizona. The primary purpose of the study was to investigate the effect of blasting energy on the crushability and grindability of the post-blast rock fragments. The crushability and grindability of the rock fragments were evaluated through laboratory comminution tests. A secondary purpose of the study was to investigate different laboratory methods for estimating the comminution properties of the rock fragments. In particular, a number of standard rock mechanics tests were conducted and compared with the comminution test results. Finally, the study was used to evaluate new technologies for estimating insitu rock mass strength and for assessing post-blast fragmentation. To estimate in-situ rock mass strength, the specific energy of drilling (SE) was calculated during blast hole drilling utilizing a continuous drill monitoring system. Post-blast fragmentation was estimated using the Split image processing system. Results from the study support the idea that increases in blast energy can enhance crushing and grinding. Also, several simple rock mechanics tests were found to correlate well with the results from standard comminution tests, which could prove to be useful in practice.

Jan 1, 2003

By John Heilig, Patrick Andrieux

"Near-field monitoring of blast induced seismic vibrations is a practical and useful way of assessing blast field behaviour for diagnosis and optimization purposes. It is also necessary in order to provide the information from which empirical vibration prediction equations, such as the one proposed by Holmberg (11 for example, can be derived. (Strictly speaking, the “near field” extends from the blasthole itself to about one charge length away from it; however, throughout this article, “near field”will.most often refer to the outer limit of this zone, from roughly 0.75 to 1.50 charge length away.) In order to obtain reliable data, proper field monitoring techniques are of paramount importance. Once the data are properly recorded, analysis can be done either in the time domain (describing vibration amplitude vs. time) or in the frequency domain (usually describing vibration amplitude vs. frequency)."

Jan 1, 1995

Numerical modelling was used to examine priming of bulk commercial explosives. Data for the HOM equation of state were calculated using a representative chemical composition, while Forest Fire model data were calculated, using a Pop plot which was estimated on the basis of existing sensitivity data, albeit for cap sensitive, small diameter explosives. The length and diameter of the primer, the location of the detonator in the primer and the shape of the primer form a set of parameters which are investigated. The effect of confinement and borehole diameter are also demonstrated, as reflections of shock waves create regions of high pressure in the explosive. The results are presented in terms of pressure and decomposition histories in the explosive and are interpreted in an engineering fashion to form rational suggestions for optimization of the priming process in the field.

Jan 1, 2002

By C. Pelley, S. Kelebek, P. D. Katsabanish, M. Pollanen

A series of small scale tests have been conducted to evaluate the effect of blasting on the grinding resistance of rocks. The samples consisted of homogeneous blocks of granodiorite and limestone while blasting was performed using single and multi hole configurations. Grinding resistance was evaluated using relative ball mill tests, rod mill tests and the SAG Performance Index test (SPI) developed by Minnovex. It was shown that the grinding resistance was affected by blasting. However the effect depended on the final product size. In the case of the coarse grained granodiorite, a negligible effect was observed for grinding below the natural grain size of the rock, while the fine grained limestone exhibited more significant changes, in the range of 13-16%. Grinding of granodiorite in the coarse size range indicated a general reduction of its work indices, as evidenced by the results obtained from the ball mill, the rod mill and the SPI tests.

Jan 1, 2004

By Tom Short

"Construction blasting covers a very extensive variety of explosive applications. I will discussseveral of these with you and then show slides from my collection, starting in 1956, which will betterillustrate the types of blasting under discussion."

Jan 1, 1991