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By Clara Godoy, J. A. Sanchidrian

In this paper, Machine Learning techniques have been used to combine data monitored from the drill rig with scanner profiles of the excavated sections to develop an automatic geotechnical rock mass characterization model able to estimate potential zones of over- or under-break of the remaining rock mass in underground blasting. By comparison of scanner profiles of the excavated sections with the blasthole positions, an Excavated Mean Distance (EMD) between the contour blastholes and the excavated profile has been obtained, which may be considered as damage measure.

Feb 1, 2020

By David Harrison, Brian Harrison

The Army Corps of Engineers completed the Charleroi Lock and Dam in 1932. It is located on the Monongahela river approximately 22 miles (35k) south of Pittsburgh in Charleroi, Pennsylvania. It is comprised of a 420-foot (128m) gated dam, and a 720-foot (219m) by 56-foot (17m) land side lock, which provides for a 16.6 foot (5m) vertical lift.

Jan 1, 2018

By Thomas Barkley

Until the recent past, blasters have provided good to excellent results with tools and processes that have an inherent error. These errors can be found in drilling, explosives delivery quality and consistency, explosives loading consistency, actual explosives performance, and pyrotechnic detonator initiator accuracy. My experience and data from several decades in the industry show the error is often times 10% or higher larger in the dimensions that measure the performance of each of these tools and processes.

Jan 1, 2011

By Jared Redyke

Thursday, October 14, 1999 marked another important milestone for America’s space program. At exactly 10:05 AM EST on a beautiful, sunny Florida morning, Dykon, Inc. of Tulsa, Oklahoma detonated approximately 300 pounds of explosives to fell the seven million pound Umbilical and Mobile Service Towers at Space Launch Complex 41 (SLC-41) at NASA’s Cape Canaveral Space Station. Completed in 1965 at the height of the Space Race to the moon, the Mobile Service Tower/Umbilical Towers (MST/UT) were part of the Titan rocket launch facilities. The MST was 265 feet high and weighed over five million pounds. The UT was 175 feet high and weighed over 2 million pounds.

Jan 1, 2001

By Chris Breeds, Larry Leone, Jerry Wallace

One of the Authors was recently retained to provide a professional engineering analysis of the potential impacts from underwater blasts used to enlarge intake tunnels at the Cheesman Dam near Denver in Colorado and to design Blast Protection Bags that could be installed in each tunnel to protect the 100- year old downstream valve structures.

Jan 1, 2012

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 Walter Jr Duke

The security of explosive materials is a vital concern to every mine, quarry and contractor engaged in blasting. Proper construction of magazines and sufficient locking mechanisms are the fundamental means of maintaining secure storage. The object of this paper is to review the proper methods of construction of storage facilities for explosives as defined by the Alcohol, Tobacco, and Firearms regulations. Subpart K subsection 55.208 and the Institute of Makers of Explosives recommendations.

Jan 1, 1991

By Paul Worsey, Gillian Worsey

The basic blasting class at Missouri S&T blast in the quarry at the experimental mine in preparation for the International Intercollegiate Mining (Mucking) Competition in April 2014.

Jan 1, 2015

By A. S. Romphf, C. K. McKenzie

Recent full-scale field studies involving single-hole charges fired to free faces under a wide range of operating conditions have delivered precious insights into airblast characteristics and propagation. The field tests involved production blasthole diameters in the range 89 to 406 mm (3 ½ to 16 in), bench heights in the range 9 to 24 metres (30 to 79 ft), burden ratios (burden/hole diameter) in the range 14 to 51, stemming ratios (stem height/hole diameter) in the range 11 to 36, explosive types of ANFO, heavy ANFO and pumped emulsion, and both solid-column and double-decked charge configurations. Around 700 measurements of peak amplitude and wave shape were made in all directions (0 to 360 deg) from the free face, from 38 single-hole tests in nine North American operating quarry/mine environments. The most striking observations were the strong dependence on directionality of the wave propagation parameters and wave frequency, the consistency of wave shape which resembled the modified Heelan wavelet, and the occasional appearance of distinct, multiple pulses from single events, shown to be echoes/reflections from quarry faces. In-hole deck charging failed in this study to achieve expected peak overpressure reductions, with the peak overpressure levels in Pascals/psi/millibars being approximately 40% higher than the as-charged weights. Inter-deck delay times in excess of around 25 ms are required for effective reduction of peak overpressure levels from front-row holes. Simple linear-superposition models based on synthetic wavelets applied to large production blasts produce composite waveforms which capture the important features of the actual pressure-time history, and correlate well with measured waveforms.

Jan 26, 2026

By A. S. Tawadrous

This paper is an evaluation of Artificial Neural Networks (ANN) as a tool in the design of the geometry of surface blast patterns. The built model uses eight different parameters, which affect the design of the pattern. Those parameters are rock type, stratification, blasthole diameter, bench height, type of explosive, priming position, powder factor and fragmentation size required. The network was trained to predict burden and spacing of the blast pattern. The model was built and trained (back-propagation technique) using 43 case histories collected from the literature. The model has then been validated using 16 cases from operational quarries.

Jan 1, 2006

By Mike Higgins

"The purpose of mining and its related industries is the removal of, and usually the subsequentprocessing of, material from the earth. This includes mining for minerals, quarrying for stone, and civilexcavations. Where this involves rock, the most common method is to fragment the rock by blasting. "

Jan 1, 1997

By S. Klerkx, R Battulwar, J Valencia, J Sattarvand, E Emami, M. Soleymani Shishvan

A new technology for energy distribution optimization, supported by NIOSH.

Feb 1, 2020

By Michael Wieland

Work-principle computations for explosions underwater or in rock reveal the way the thermodynamic characteristics of surrounding material influence the resulting shock and heave. To reach total thermodynamic equilibrium under such transitory dynamic circumstances, reactions must quickly readjust to changing circumstances, which works for molecular (military) explosives where the fuel and oxidizer type atoms are originally in close proximity. For non-molecular mixtures with their dispersed zones of oxidizer or fuel, in particle or droplet form, there are numerous unproductive collisions, increasing the wait time required to reach chemical equilibrium. Underwater test data for molecular explosives compare rather well with the shock and heave resolved from the work-principal model, while the non-molecular explosives normally used in mining tend to yield a noticeable discrepancy. Years ago, it was recognized that the underwater shock was lower than expected and the heave was higher than expected for ammonium nitrate fuel oil (ANFO), though their resultant sum for the total work was roughly what was expected. When the readjustment of thermodynamic equilibrium warrants quicker chemistry than occurs in underwater or rock shooting, the time-retarded chemistry reduces the shock and raises the heave within the surrounding material without reducing the total work, unless the reaction retardation is quite severe. This technical complication in reality is a nonequilibrium issue that is difficult to resolve with just thermodynamics, though a rational set of transformation factors is formulated herein to represent those circumstances.

Jan 1, 2008

By Luis Huaroc, Augusto Sotomayor, Erick Rodriguez, Paulo Fernández, José Ricaldi, Luis Alejandro

The application of the Kuz-Ram model for the prediction of fragmentation is used worldwide, in Coimolache Mine it was used to determine blast domains and optimize the process by obtaining drilling patterns that meet a required X80 and reducing the uncertainty of drilling.

Feb 1, 2020

By Ken Eltschlager, J Silva Castro, J. M. Hoffman, Braden Lusk

This case study focuses on analysis of sounds inside a house induced by blasts as result of surface mining coal in West Virginia and how to better communicate technical information to the public. The field study included a house wide vibration and sound monitoring system installed in a home which was subjected to blasts at varied distances and direction. The structure response was separated into ground vibration and airblast induced movement due to the differences in their times of arrival. This signal was then compared to the sounds recorded to determine which component of blast (ground vibration or airblast) induced the maximum sound. Findings shows that blasts at distances less than 762 meters (2,500 feet) had maximum sound responses from both ground vibration and airblast. While for blasts beyond this distance the maximum sound response was caused by ground vibration without exception. The kitchen generally created the most sound. The second phase of the study was to gauge the public’s response or preference to technical information. Three hundred and forty eight (348) telephone surveys were conducted in Logan and Boone counties West Virginia. Based on the survey, the public prefers units of pounds per square inch (psi) for airblast and millimeters of displacement for ground vibration. Ultimately a public relations plan was developed based on the results.

Jan 1, 2012

By Brent Blanchard

The use of explosives to safely fell structures can be traced back over 300 years. Since then, dozens of chemists, inventors, blasters and demolition experts worldwide have played prominent roles in the evolution of what has become the modern-day explosive demolition industry. In America, one of the earliest applications of explosive demolition occurred in response to the great fires of San Francisco, where homes and businesses were blasted with gunpowder in a desperate attempt to create firewalls. Later in the 19th century, inventions such as nitroglycerine, dynamite and blasting caps made structural blasting a safe, efficient alternative to conventional demolition methods. The 20th century brought the first experiments in shaped charge technology, and this, combined with developments in portable seismology and non-electric delay systems, allowed an ever-expanding variety of structures to be explosively felled by demolition experts throughout the country. The 1950s and .60s brought a new wave of commercial structural-blasting entrepreneurs (several of whom are still active today), and their efforts towards improving adjacent-structure protection and public relations beget the felling of large commercial buildings in dense urban environments. By the late 1980s, publicity-driven motives were gaining greater influence in the decision to .implode. various structures, and the transformation of blasting operations into promotional spectator events played a role in several injuries and fatalities. Since that time, however, a renewed sense of responsibility practiced by most blasting firms and project officials has resulted in the safe, successful completion of hundreds of recent endeavors. In sum, what appears today as an efficient, economical - and visually spectacular - way to demolish structures has its roots in developments of the past several centuries

Jan 1, 2002

By Donna Kliche, Charles Kliche

It has been previously documented that various weather conditions such as wind direction and speed, cloud cover and, especially, temperature inversions can significantly affect the overpressure generated by a blast event (Siskind et al, 1980; Oriard, 1999; Siskind, 2000). The overpressure can be magnified downwind and reduced upwind; a change in the regular profile of temperature with elevation can magnify or focus the sound intensity at some distance from the blast event.

Jan 1, 2011

By Carlos Campos Junior, Leonardo Soares Chaves, Raul Carretero Hoz, Renato Jacome Costa, Davi Bastos Martins de Oliveira

The Vale’s Serra Sul mine, also known as S11D project, is one of the world’s largest open pit iron ore mines, located in Brazil’s Amazon region. The mine produces around 90 Mt of high-quality iron ore annually. Its unique orebody enabled the S11D project to adopt a truckless mining system with In-Pit Crushing and Conveying (IPCCs) for ore exploitation and waste stripping. The IPCCs system requires crushing the waste, mainly composed by the jaspilite lithology, and is also conveyed to waste deposits several kilometers away from the mine. Due to Amazon’s environmental restrictions, the project was designed with preliminary geological knowledge, leading to the installation of primary crushers not designed for the hardest jaspilite, with uniaxial compressive strength (UCS) up to 500 MPa. This resulted in low waste crushing performance, affecting stripping ratio and threatening future production. A project was developed to improve the fragmentation of the jaspilite, allowing higher waste IPCC production, and reducing the risk to the production due to low performance of waste crushing and conveying. The first challenge was the independence of the geological and the geomechanical models, while only the geological model was considered in blast designs, the geomechanical model describes six waste groups of jaspilite classified according to their strength. A new geological model was then created to incorporate the geomechanical classification, allowing different blasting design according to the rock strength of the jaspilite. The blasting pattern on most compact jaspilite was reduced 27%, from 22m² to 16m² in 9 7/8” diameter holes, with a proposed theoretical reduction of 23% of the P80, from 326mm to 250mm. The second challenge was the implementation of the new design, as this pattern size and the high powder factor (2.9 kg/m3) were paradigms for such a large iron ore mine. The measured results have shown 25% reduction of the P80, the crushing rate was increased by 17% (230t/h), saving around $2.4 million annually in crushing and conveying system maintenance.

Jan 21, 2025

By K. Hausmann, P. A. Sashin, G. J. Prejean

Misfires caused by unreliable shock tube constructions can have significant cost implications and place field workers at serious risk during remediation. Ionomer materials, used as a subtube in shock tube constructions, provide superior hot tack strength, oil resistance, impact resistance at cold temperatures and excellent thermoformability properties. These are important features for resisting blast-throughs and ensuring blasting reliability in demanding environments, such as open pit mining in harsh environments. Superior hot tack strength, strain hardening, and excellent thermoformability properties of the ionomer materials ensure uniform powder distribution along the shock tube during construction and avoid undesired powder accumulation due to deformation or vibration during use. Oil or chemical resistance is another feature of Ionomers. This allows improved property retention in contact with oils and hence longer sleep times of the shock tube. Another feature of these highly engineered ionomers is superior impact strength at low temperatures. This plays an important role considering the resistance to fly rock impact in open pit mining operations in particular in cold climates.

Jan 1, 2011

By G. Walsh, L. Wolkovitch, A. Savage, V. Romero, T. Zimmerly, G. Imahara, J. Hyneman, K. Byron, D Tapster, S. Belleci, J. Metzger, M. Stanley

Testing was conducted at the Energetic Materials Research and Testing Center for the MythBusters on three separate occasions. This testing included (1) an experiment designed to create diamond from graphite using the shock and pressure of a detonation, (2) the flattening of a car using a steel plate driven by a rocket sled, and (3) the bifurcation of a car also using a rocket sled. All tests were successful; diamond was produced following the detonation of ANFO, and extracted from a graphite / cobalt matrix. A plate was accelerated to 646 mph (1040 km/hr) using a two-stage sled system loaded with 5” (12.7 cm) high velocity aircraft rockets (HVAR) into a car, which was subsequently demolished. Finally, a steel wedge was pushed to 541 mph (871 km/hr) by a one stage sled using HVAR rockets, and was able to cleanly cut a target car in half.

Jan 1, 2010