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By P A. Lang, J G. Ayotte, R W. Humphries

Atomic Energy of Canada Limited (AECL) has the responsibility for research, and development of technologies, for the safe and permanent disposal of Canada's nuclear fuel wastes. As part of this comprehensive program, AECL is constructing an Underground Research Laboratory (URL) near Lac du Bonnet, Manitoba, to evaluate aspects of the concept of waste disposal deep in stable geological formations. No nuclear wastes will be used in the URL program.

Jan 1, 1986

By Sang Ho Cho, Masaji Kato, Masaaki Yamamoto, Masaaki Nishi, Katsuhiko Kaneko

This paper presents a numerical simulation method to predict rock fragmentation and to verify a fracture mechanism by bench blasting. The rock fragmentation, which has been used as a means of the index to estimate the effect of bench blasting, affects the expenses for loading, conveyance and crushing of blasting muck piles. The developed numerical simulation method is based on the finite element method and fracture mechanics and includes the re-meshing procedure to express the fracture process of the rock mass. This paper discusses a procedure for a determination of size distributions of the results, which were calculated by numerical simulation, including the tines.

Jan 1, 2002

By Janice K. Means

The purpose of this paper is to provide the seminar attendee with: information on pipeline construction, operation and standards to better equip him (or her) to analyze the ultimate effect of blasting stress on pipelines; an introduction to the analysis of blasting effects to pipelines using the American Gas Association analysis method; and; supplemental sources useful in the analysis of blasting effects to steel pipelines, and, in particular, on natural gas pipelines.

Jan 1, 1992

By J E. (Boet) Coetzee

SAFEX International, as the name suggests, is a global organisation, which has the fundamental objective of improving the safety of operations concerned with the manufacture, storage, transport, and use of commercial and military explosives and pyrotechnic products throughout the world. It is a nonprofit making organisation of manufacturers of explosives from all parts of the world, founded in 1954 with the aim of exchanging experiences within the explosives industry. Every third year SAFEX organises a Congress during which members present papers on selected themes and discuss reports of significant incidents that occurred since the previous Congress. Admission is for SAFEX members only, thereby creating a safe environment for discussing problems “within the family”. The XV Congress will celebrate the Association’s 50th anniversary in Geneva where it was founded. An overview of the Congress indicates its structure and covers aspects such as the training event, technical seminars and the themes for the plenary sessions and associated workshops. The paper also highlights the special event for the chief executives of member companies and the review of incidents that occurred in the industry since the last Congress. The Congress concludes with a social programme for delegates and their partners on the last day.

Jan 1, 2005

By Ron Frye, Carl Liibbe, Wayne Curtis, Julie Pecori, Dan Leach

Test work comparing the performance of a Low Density Porous Ammonium Nitrate Prill to regular Porous Ammonium Nitrate conducted in Pennsylvania and New York showed that less ammonium nitrate was required to perform the same work and that improved sensitization of an emulsion/ammonium nitrate blend reduced “orange fumes”. Fragmentation was similar in all tests with improved heave and throw experienced.

Jan 1, 1997

By Luis Valentim, John E. Wiegand

Highwall or face profiling has long been used to facilitate the design and placement of front row blastholes to ensure optimum burdens. Traditionally, a large number of laser measurement points obtained from the rock face or highwall, were input in profiling software packages. This method can be time consuming and requires access to the rock face with a complete view of the highwall, to be successful. Stereo photography has also been used to generate the rock face surface, but this method also requires access to the highwall (and pit floor in some instances) for measurement of reference targets or points.

Jan 1, 2016

By Travis Davidsavor, David Provost

A segment of high-pressure steel petroleum pipeline needed to be replaced on a hillside and beneath a waterway within an existing right-of-way containing multiple petroleum pipelines. The pipeline replacement required excavation of sedimentary rock to allow placement of the new pipe. As a result of an existing right-of-way limitation, steep slopes, and hard rock, blasting would be required as close as 7.8 meters (25 feet) from two operating pipelines. Existing pipeline company standards would have effectively precluded the construction of the replacement pipe by blasting rock. To facilitate the required construction and evaluate actual pipe stress during blasting to ensure pipeline integrity, a comprehensive evaluation methodology was developed by a team of pipeline, mechanical, geotechnical, instrumentation, and blasting engineers. A total of 60 strain gages were affixed to the steel pipe and seismographs were buried at the surface near the blasting area. Test blasting allowed pipe stresses with corresponding ground motion to be monitored. A conservative analysis approach evaluated individual peak strains and revealed that only small pipeline strains, and therefore stresses, were induced in the pipeline as a result of blasting. This evaluation allowed specific procedures to be developed to inform the blasting operation of maximum explosive loading and minimum charge distances. Additionally, this effort provided the pipeline operator with appropriate pipeline operating pressures during blasting activities to limit total stresses in the pipeline to be below allowable stresses imposed by code, regulators, and company operational limitations. Recommendations were developed to measure the blast generated ground vibrations with seismographs buried at the depth of the pipe, near the pipe, and limit the ground vibrations from blasting to 150 mm/s (6 in/s). If ground vibration intensities of 120 mm/s (4 in/s) or more were observed, additional engineering review is recommended. Finally, all blasting would be suspended and all activities reviewed at peak ground vibration intensities of 230 mm/s (9 in/s). The evaluation effort resulted in effective and efficient construction of the pipeline replacement and allowed the pipeline operator to better understand blasting induced stresses on their assets.

By Peter Stamos

In the summer of 1989, Material Service Corporation (MSC) was expanding its Thornton limestone mining operation putting them in close proximity to two shopping centers in Homewood. In other communities, similar expansions had been met with community protests and lawsuits seeking injunctions to stop operations.

Jan 1, 1991

By Douglas Rudenko

Have you ever had a neighbor complain about a blast one day, but says the next day’s blast was better, even though the Peak Particle Velocity (PPV) increased? How about neighbors that complain about a small trimming shot, but don’t complain about a big production shot? Have you ever reduced the pounds/delay and gotten more complaints ? Mine operators are often bewildered when trying to correlate blast design parameters to homeowner complaints. When complaints come, standard practice is to set up a seismograph in the neighbor’s yard to monitor the blast. Immediately after the blast, the neighbor usually reappears from the house wanting to know the seismograph reading. When told that the PPV was 0.1 in/set, well below damage levels, the homeowner explodes saying “Your machine is wrong”. Perhaps he is right. Understanding why people complain about blasting is not about PPV, it’s all about structural response. People could care less about how much the ground vibrates; they only care about how much their house vibrates. In this paper we will examine the primary factors that control structural response. Through the use of a large array of digital seismographs, the effects of two production blasts on a community surrounding a quarry are studied. The predicted structural response resulting from each blast is calculated at 175 seismograph locations. The predicted response is then correlated to previous research on human perceptibility to vibrations. The results of this analysis and correlation give a better understanding of what the residents actually feel in their homes. The detonations of two single-hole signature blasts are also recorded by the array of seismographs revealing the dynamic characteristics of the geology ‘surrounding the quarry. Once the influence of the geology was understood, blasts were configured to disrupt the natural rhythm of the site through the use of millisecond delays.

Jan 1, 2000

By K Taylor

Small scale tests have been conducted in blasting vessels in the laboratory, where the effects of explosive composition, charge diameter, explosive confinement as well as additives to the explosive were examined on NO, NO2, CO and CO2 production. Fumes were analyzed continuously using a flue analyzer, providing analysis every 15 seconds. The results were compared to previous work conducted in the laboratory and to literature findings. It was found that the type of the explosive was the most dominant factor with emulsion explosives producing significantly less amounts of toxic gases. ANFO was shown to always produce nitrogen oxides, even when fuel rich. Tests were also conducted by detonating explosives in broken rock, simulating the release of products of detonation during the formation of a muckpile. Products of detonation were affected by the presence of atmospheric air or rock around the charge. Gaseous products of detonation migrated through the rock piles at different rates, resulting in a change of toxicity values over time. In the small scale experiments, CO appeared to travel faster than CO2 while NOX was not identified. Analysis of the gases that were released during digging, several hours after the blast, resulted in high temporary concentrations of toxic fumes.

Jan 1, 2014

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 Gordon Revey

The challenge of managing blasting risk, types of risk, public perception, and a system for managing risk were covered in the first part of this article in the May/June 2000 issue of the Journal of Explosives Engineering. This final part of this two-part series provides a method for identifying specific blasting risks and reviews the importance of community relations.

Jan 1, 2001

By C Agreda

The Cushion Blasting Technique applied to solve the high risk case history represented by a 10,704 TM rock locate at 120 M from the hydroelectrical plants of 350 KV each, is described, analyzed and discussed. The generation and distribution of 700 KV produced by two hydroelectrical plants must not be interrupted by any reason, because the 26 district of the province of cajatambo, of the Lima department; would not have electrical power. The search of the best alternative and methodology, the drilling and blasting pattern calculations, charge design and loading, connections and initiations of the 50 blasts are described, analyzed and discussed. Finally, the excellent results from a technical, economical, enviromental and safety point of view of the 50 primary blasts are discussed and emphasized.

Jan 1, 2005

By Phillip R. Mulligan, Kevin Gantz, Aaron J. Ward, allen shirley, Sean Treadway

Understanding the impulse transferred into a structure by the coupled two-phase loading produced by an explosive charge buried in soil is of interest for various applications. The most common impulse measurement technique involves a buried explosive charge and a steel plate/test structure suspended above the charge. Upon detonation of the charge, the soil and overpressure heave the plate into the air. The plate’s trajectory and velocity provide the necessary information to calculate the total impulse transferred from the charge configuration.

Jan 1, 2016

By M. Ganster, H. Krenn

The mission of the project is the fast and cost-effective rehabilitation of decommissioned lignite mining and coal upgrading facilities. This is necessary to ensure the successful future utilization of these sites. On the one hand, for founding new industrial and commercial facilities and on the other hand for touristic activities.

Jan 1, 2013

By T Goswami

The conventional practice in open cut coal strip mining has been to blast the overburden or coal layers in separate blast events. This is done in order to maximise the benefits from throw blasting and also to limit coal losses. Each blast event usually has a particular design of hole diameters, burdens and spacings, explosive charges and blast timing in order to achieve the required blast outcome for either the overburden or coal. This means that each blast has to be separately cleaned on the surface after excavation of the previous blast. Hole locations then have to be individually surveyed and marked, holes drilled, explosives and initiators loaded and the blast fired. Each of these actions takes considerable time and resources and therefore impacts on mine productivity. The mine has to be cleared for each blast event and every blast presents a new potential source for noise, dust or vibration disturbance to the neighbouring population. Exposed highwalls are also subjected to vibration and damage from each subsequent blast event

Jan 1, 2006

By Nolan Eckroade, Nigel Pereira

Wireless electronic blasting systems are a new technology that enable truly wireless initiation through rock, air and water. This is achieved using low frequency magnetic induction waves to wirelessly send a firing command to groups of in-hole primers. Fully wireless initiation not only removes the limitations imposed by a wired connection to each primer in a blast, but also enables users to alter the paradigm of conventional mining techniques to advance operational productivity and reduce personnel exposure to high-risk activities. While initially deployed in underground applications, wireless electronic blasting is now being used in the open cut environment. To capture the early impacts in surface mining operations, case studies conducted at three surface mines evaluated blasts utilizing a wireless electronic blasting system against baseline blasts using conventional, wired initiation systems. The purpose of this paper is to outline the specific learnings associated with wireless electronic blasting in surface mining to date. The paper will include references to these specific case studies as well as benefits realized and applications for the future.

To meet the energy requirements, hydroelectric projects are planned and executed in many countries. Though these projects requires a high capital investment, the returns are regular with minimum maintenance after commissioning of the project and are ecofriendly. Bhutan is situated in the eastern Himalayas and covers an area of 38,394km2 (14824.01sq. miles. It is bordered by India in East, South and West and by Tibet in the North. The hydropower potential of the country is estimated at 30,000MW, out of which around 5% has been harnessed.

Jan 1, 2016

By Francisco Sena Leite, Pedro Brito, Gean Frank, PhD Soeiro de Carvalho, Jose, Vinicius Miranda

The consequences of rock blasting with explosives are directly related to the accuracy of drilling and, because they have an effect on fragmentation and ground level, they should be controlled to ensure a problem free production, increase work safety and reduce environment impact. Safety control is one of the most important processes in detonation, since it can compromise the worker security on site and, eventually, neighboring communities. Due to the technology advancements, it is possible to build a hole deviation control device with “of the shelf” parts, and for that reason the authors decided to evaluate the possibility of measuring hole deviation by creating a portable prototype using an electronic sensor capable of measuring the acceleration on objects, that is, to measure the own acceleration of a system, known as "accelerometer" and a micro-controller to handle and treat data. The main idea behind this paper is to validate the power of the Euler method, given the stepping limitations of the sensor and micro controller in order to reproduce of the hole shape. A case study was carried out, comparing the measurements of borehole deviations made by a traditional equipment and the prototype. A mobile application was also created in order to recover and treat and display the data to the user. For validation of the prototype, several holes were measured using the two devices. A residue analysis was used to validate the data obtained. After analyzing and confirming the effectiveness of the new equipment, the normality tests prove a symmetric distribution with null expected residual mean and minimum variance. Consequently, the accuracy of the prototype is evidenced. Thus, the authors aspire to emphasize the potential of using these sensors allied to a traditional numerical method for analysis of hole deviation.

Jan 1, 2019

By Stewart A. Silling, Dale S. Preece

The two key results of rock blasting are fragmentation and movement of geomaterials. Movement/flow of the blasted rock is often referred to as heave. Modeling the movement of full scale blasting is now possible with 3D distinct element models and parallel processing.

Jan 1, 2016