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By William C. B. Gates

Demolition blasting next to an active railroad can be very challenging because of track safety, blasting vibrations, potential track fouling by blast debris, and short work windows on a live track. Recently, in eastern Washington, one of the major railroad companies has been aggressively constructing a second main track to accommodate the expected increase in rail traffic of natural resource products. To accommodate construction of the second line, the railroad company used blasting demolition techniques to remove an old railroad trestle pier on the Milwaukee Road that was in the footprint of the new track bed. The trestle bridged the present rail line and flanked the track with two massive 550-ton (499 tonne) twin-columned steel reinforced concrete piers. The railroad contracted with a specialized contractor to remove the south pier using blasting demolition techniques. The blasting design presented the following challenges: blasting during live track conditions and short work windows; designing a V-notch blast pattern to ensure the pier fell away from the live track; drilling, loading, and timing of the shot; maintaining blasting vibrations at the track below 4 in./sec (102 mm/sec); maintaining ambient overpressure noise below 133 dB; control of fly rock and debris; and track protection and emergency debris removal plan.

Jan 1, 2016

By John L. Floyd

The use of explosive energy to displace overburden or waste material can provide substantial savings to operations which normally rely on mechanical means for material removal. To optimize the available explosive energy, it is important to quantify the rock's response to the type of explosive and explosive accessories used. During a blast, rock breakage and movement occur so rapidly that the naked eye cannot detect the details of the fragmentation process. A relatively high speed motion picture camera (500 frames per second) can provide the extended time base needed to analyze in detail the site-specific rock response to the explosive detonation. The data of importance to blast casting that can be quantified from these films includes initial face movement, trajectory of rock, and differential face velocities of the material shot. In addition, the ground swell velocities, stemming confinement, and stemming ejection velocity can be determined. The performance of explosive products and delay element accuracy can also be ascertained. The use of high speed motion picture photography and analysis can reduce the number of field trials necessary to maximize explosive performance and increase the benefit provided by blast casting, and in turn, lower production costs. This paper will discuss the methods used for data accumulation and analysis. In addition, three field studies conducted at three separate mining operations will be presented.

Jan 1, 1988

By Mattos J. L. C

Drilling and blasting with explosives in mining operations near communities require careful planning to mitigate socio-environmental impacts. Ground vibration, noise emission, flyrock, and dust dispersion are factors that may trigger conflicts with local populations. However, large-scale operations demand high productivity and intense material handling, making it essential to balance operational performance with impact control. The adoption of best practices, combined with advanced monitoring and mitigation technologies, enables sustainable mining even in proximity to inhabited areas. This study proposes the use of double and triple-deck blasting techniques with large-diameter boreholes (12 ¼” – 311 mm), addressing the sizing of charges and decks, as well as measures aimed at reducing noise perceived by nearby communities. The approach seeks to maintain the use of large drilling rigs already present in the operation, avoiding costs related to premature equipment replacement or expensive alternatives, while minimizing environmental and social impacts and promoting a more balanced and responsible mining model.

Jan 26, 2026

By Dale S. Preece

"Detonation delay timing has been an important aspect of quality rock blasting for decades. Detonators that enable delay timing have improved over the years especially with the recent advent of precision electronic detonators. The positive effects of precision delay timing have been observed repeatedly in the field with improved fragmentation, heave and overall blast control. Three-dimensional computational capabilities in terms of software, material models and computer speed have recently made possible the computer simulation of multiple blast holes in a bench configuration with precise delay timing between holes. Some of the key physical phenomena enabled by precise delay timing include: 1) collision and interaction of stress waves produced by adjacent blast holes, 2) reinforcement of stress waves from multiple holes as they reflect from the bench face and ground surface, 3) reflection of stress waves from “dynamic free surfaces” created by previously detonating holes, and 4) deformation induced fracturing, cracking and fragmentation. Simulating rock blasting in 3D has shed light on the physics involved and is resulting in an evolution of our understanding of fragmentation mechanisms. Routine use of these 3D computational tools will result in a much better understanding of the complex physics set in motion by the rock blasting process and allow predictionof improved blasting."

Jan 1, 2009

By Evan Boone, Peter Bellairs

A technical services visit was conducted to determine the initial parameters to successfully presplit several benches for an input crusher installation at the Wolffdene quarry. The paper details the preliminary design utilising both detonating cord only and specialised presplit product charges and compares these to the final designs utilised based on site experience. The role of accurate drilling, explosive loading and geology in obtaining successful cost effective presplits is highlighted.

Jan 1, 1998

By Dennis L. Paisley, Thomas P. Turner

Laser slapper detonators are the next generation detonator under development at the Detonations Systems Group at Los Alamos National Laboratory and function very similarly to an electrical slapper. A fiber optic transmits a laser pulse to ablate a thin metal film. This film, or flyer as it is commonly called, is launched through a short barrel to km/s speeds. The flyer shock loads or slaps a high density pressing of secondary explosive, setting off a detonation therein. Laser slapper detonators afford a number of safety advantages over other conventional detonators. Most important they require very high peak laser powers to operate, orders of magnitude larger than possible sources of natural or man-made accidental stimulus. Because light is transported over fiber optics, laser slappers avoid many of the electrical hazards associated with detonators. Use of insensitive, secondary explosives makes these detonators safer to handle, manufacture, transport, and deploy.

Jan 1, 1994

By Brian Carr

This workshop will display all of the existing products that are available as stemplug devices and discuss the general concept of the use of them. Actual results will be discussed along with several case histories. There will be adequate time for questions and answers.

Jan 1, 2000

By Douglas Rudenko

Most engineers, mine operators, or contractors acknowledge the importance of having accurate subsurface information in order to plan a project or solve a problem. Conventional methods of exploring the subsurface such as augering, core borings, or test pits can provide information, but it is often costly and sparse. Geophysical methods offer an alternative to help supplement sparse information~ gathered through conventional exploration techniques.

Jan 1, 1998

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 Lazar Kricak, Zoran Teodorovis, Dragan Bogunovic

Scattering of delay interval around nominal value is an important issue in blasting practice. The scatter interval, as becomes wider, increases a probability of time delay overlapping adjacent blastholes. An excessive flyrock, ground vibrations, air blast and poor fragmentation are the symptoms for scattering related problems. Utilization of the short delays in the blastholes and longer delays on the surface are recommended solution to overcome mentioned problems. In contrast to global trends manifested through the application of electronic detonators and non-electric shock tube systems, revitalization of inexpensive electric detonators in combination with an accurate initiation system may be an acceptable solution. An extensive work was carried out at the Blasting Center Laboratory at the College of Mining and Geology, University of Belgrade, to develop a precise initiation system. As a result, Sequential Blasting Initiation System – Radio Frequency (SBIS-RF) was developed. It is expected that this system will increase blasting productivity, and reduce negative environmental impacts and total blasting costs.

Jan 1, 2008

By John Watson, Tom Treleaven

This guide presents nur-nerous patterns that provide 8 millisecond separations between initiated charges. The guide is tabulated in seven sections to provide Quick reference by number of decks or bunch blasting. The pattern IS presented in the section where the highe!$ number of decks works. It should be noted that patterns applicable to multipledackshwtings are alsoapplicsblefor fewer decks.

Jan 1, 1995

By Carl Hendricks

Aquila Mining Systems Ltd., is the world leader in drill monitoring, control and GPS-based machine navigation systems for the mining industry. This paper will review the design and application of AQUILA’s drill monitoring, control and positioning systems currently in use throughout the world and some of the benefits that derive through their use. In 1993, AQUILA became the first company to install a high precision, cm level, real-time GPS receiver on a blasthole drill. In fact, this was likely the first application of GPS on any form of production mining equipment. To date, AQUILA has installed over 90 GPS based drill monitoring systems worldwide. Since 1992 AQUILA has continued to lead in the advancement of new technologies for drilling including real-time geology recognition and automated drilling control systems. The AQUILA DMseries drill systems offer mines the ability to collect and transmit to the mine office; drill production statistics, ore and waste intersections, exact collar elevations, hole positions and depths, maintenance information and consumables tracking. Unique office software developed by AQUILA provides an encompassing Windows environment within which to manage and coordinate all aspects of data communications and information management between the drills and various mine departments. AQUILA and Caterpillar, along with Mincom and Trimble Navigation are partners in a technology alliance that is providing the surface mining industry with vehicle tracking and navigation systems for all mobile production equipment.

Jan 1, 2000

By Greg Parker

"As the Explosives Industry continues to evolve and condense, those involved, such as Blasters,Contractors, Distributors and Consultants, continue to be challenged by both internal and externalforces. Increased pressure by government agencies, higher safety standards, new levels of technology and mandatory certification programs, are forcing us to expand our awareness and increase our levels of efficiency. These higher standards require increased awareness. Increased awareness requires better training programs and better supervision with emphasis on production and the employee. This means the desire to improve must be instilled from the top down. this paper will explore the current impediments to this goal and discuss the possible solutions for achieving greater safety awareness, increased production and higher levels of personal achievement. Through the use of audio/visual aids, I will attempt to show the discrepancies as well as the solutions."

Jan 1, 1999

By Thierry Bernard, Pierre M. Vuillaume, Michel Kiszlo

"In the context of its studies for the trench ministry of the environment and for the French national coal board, INERIS (the French institute for the industrial environment and hazards, formerly CERCHAR) has made a complete critical survey of the methods generally used to reduce the levels of blastingvibrations."

Jan 1, 1996

By Daniel Roy

This paper introduces a new, safer bulk emulsion loading system for underground mining operations. The features and benefits of the equipment, along with the use of Dyno Nobel Inc. patented gassed emulsion technology, is summarized in the application of a stope blast with very difficult and complex ground conditions. The paper describes methods used to optimize the amount of energy required to break the ore while protecting the integrity of the surrounding backfilled pillar.

Jan 1, 2003

By Hector O. Romero, Paulo C. Fernández A, Claudio C. Gajardo

Phase 06 of the Los Bronces mine, currently under extraction for development, has the particularity of being close to the installations and buildings of a neighboring copper mine. Therefore, the blasts must ensure the continuity of the operation without affecting the nearby structures of the neighboring district, which include Maintenance sheds and Warehouse. Specifically, the safeguards consider a scenario that includes: - Flyrock projections (<150m) - Edge profile studies - Vibrations according to the NCh3577 standard - Nitrous gases Additionally, Phase 06 is also within Los Bronces, so strict control over spillage into the pit is necessary to avoid blocking ramp access to this level. The challenge lies in protecting not only the operation and facilities of the neighboring mining district but also the operability of Los Bronces. Thus, addressing these considerations, blasting configurations are developed with prior simulation of vibration models, flyrock, and spillage in all blasts, with strict control of technical design and implementation to ensure the results. Currently, blasts are successfully executed with control of projections based on the proximity of the projects, vibration (<40mm/s) with decoupling of holes of 17 mm/s between holes, reactive rock tests for explosive selection (loading advancement), and spillage simulation inside the pit according to the loading design; thus, ensuring operational continuity and mine development.

Jan 21, 2025

By Thierry Bernard

This case study shows how a unique combination of field measurements and advanced technologies allowed blasters designing, loading and firing an incredibly challenging quarry blast.

Jan 1, 2015

By B T. Lusk, Jhon J. Silva

"The original signature hole technique to predict vibration levels from blasting, is based on theassumption that each hole in a production blast, generates an identical vibration waveformarriving to the point of interest. When the same waveform is used to represent the vibrationproduced by each hole, the complete waveform for the whole blast is the convolution betweenthe waveform and the impulse sequence that represents the initiation timing of the blast. In thisresearch, several field tests were developed to establish the validity of the invariability of thewaveform hole-to-hole in a mining production blast. The results of the tests showed that thereare variations in amplitude and frequency content for the hole-to-hole waveforms. Thevariations can be explained due to the character of the parameters involved in a production blastbetween them: different vibration path for each hole, differences in the geometry of each hole,differences in the explosive charge for each hole (chemical and quantity), etc. This paperdescribes a methodology based on the main characteristics in both; time and frequency domainof any recorded signature waveform and uses Fourier series to approach one equation to generatedifferent random waveforms for each hole that can be used in the prediction of the completevibration record of the blast. The methodology is the base for signature hole analysis using aMonte Carlo scheme."

Jan 1, 2012

By Martti Hagfors, Jussi Saavalainen

The underwater explosions has been used as a test method for the determination energy content of explosives. The test method is suitable for all kind of explosives; homogeneous, heterogeneous, wa-ter-resistant, no-water resistant, cap sensitive, booster sensitive, explosives with hard confinement, explosives without confinement etc. It is also the only test method by which shock, gas heave and to-tal energy values of the explosives can be measured separately. This feature makes it possible to use the test method to develop the explosives for different purposes; the military high explosives need more shock energy where as the gas heave energy is very important feature for the blasting and sea mine explosives.

Jan 1, 2010

By Bruce Vandenberg

A 3D, PC based computer program is currently under development by Blasting Analysis International, Inc., to analyze the kinetics of full scale blasts with two or more high-speed motion picture cameras.

Jan 1, 1990