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By Benedict C. Di Duca

In the underground construction industry. when bidding work, not only is the contractor faced with determining if rock: is in existence within the parameters of his work. he must also estimate the quantity and the most efficient method of removal.

Jan 1, 1990

By Jerry Newton

The bulk explosives industry is relatively young compared to how long explosives have been in use. It's been around for about forty years, about the length of a person's career. This period of explosives history has seen constant change. The type of product, the manufacture and the trucks that haul it have changed a great deal over the years.

Jan 1, 1997

By Bradley C. Paul

Similar rock formations exhibit great variability in resistance to fragmentation during crater blasting. This observation was made during an attempt to calibrate the Kuz-Ram blast fragmentation model for crater blast geometries used in a modified in situ mining method for copper. The KuzRam equation is used to predict the fragment size distribution from blasting and includes a term called the "rock factor" to account for the fragmentation characteristics of the material. A data base of field scale crater shots in oil shale was available to supplement more limited data on copper ores. First, the blast geometry terms of the Kuz-Ram formula were modified to fit field data with various crater blast geometries. Rock factors were chosen to center the predicted curve on the curve representing observed fragmentation. Next, five possible sources of variability in rock factor were investigated: the grade of the oil shale, the aspect ratio of the charge, the type of explosive, the charge depth, and the rock itself.

Jan 1, 1989

By Stuart Brashear, Lee Schettler

"The effect of water on several ANFO/emulsion blend ratios is documented by both physicalobservations and analytical testing to demonstrate the effect even small quantities of water canhave on water resistant blends."

Jan 1, 1996

By Clifton W. Livingston

This paper is the first of a series in which evidence suggesting a quantum mechanical behavior of materials in blasting and high energy impact loading is presented. Such evidence relates the mechanical behavior of materials to their electro-magnetic behavior at successive stages in the development of the electric and magnetic fields as the disturbance proceeds outward from the borehole in blasting.

Jan 1, 1981

By Zhang Yangde

"This paper reports the clinical research work of Micro-explosion of Biliary Calculi . In theprogram the technique of directional micro explosion applied to disintegrate the biliarycalculi of body and decreases the rate of operation. Up to the present, 235 cases of biliaryduct calculi have been successfully treated by use of implusive force of micro-explosion .The success rate of blasting stones was 100% by the use of the directionalmicro-explosive instrument made by us , the once success ratio of micro-explosion was93.2% and tl~o rmulb of treatment were satisfactory. . Considering the density of theblood vesselsiD the human liver, limitation of space in the h~patic.ducb, the securiey andadaptation, we have designed two types of micro- explosives equipment called ZS device,electric initiation and nonelectric initiation to initiate explosion. The head diameter of thedevice ie 1.5-1.8 mm . It is applicable to all kinds of fiber endoscope by inserting ZSdevice under grossing eyes or TV set ."

Jan 1, 1993

By T I. Jerman

The Du Pont "Detaline" nonelectric initiation system utilizes a low energy detonating cord. It is compatible with conventional detonating cords and shock tube downlines as well as nonelectric in-the-hole delay caps. "Detaline" millisecond surface and in-hole delays offer a great degree of flexibility in developing effective delay patterns for improved fragmentation and reduced vibration. All components are easily assembled in the field.

Jan 1, 1982

By P A. Gibson, J R. Brinkmann

The South African gold mining industry fires approximately 800 000 sloping blastholes daily. A programme aimed at characterizing the stope blasting process is underway in order to identify areas for improvement and to provide blasting related information for the design of mechanized sloping systems.

Jan 1, 1985

By T Michael LeBlanc

Drill trajectory deviation is a recurring problem in vertical retreat stoping operations. As a result of this deviation, 60 kilogram (165 millimetre diameter) and 103 kilogram (302 millimetre diameter) explosive charges are routinely detonated beyond ore/waste contact zones. Consequently, there follows a reduction in finished stope wall stability and an increase in ore dilution.

Jan 1, 1996

By Teele Tuuna, Voglers Eesti OÜ

Blasting operations are a strong and important part in any kind of building and mining industry, a shot-firer profession is one of the oldest professions in the civilized world. It still serves an important and ongoing purpose in the modern economy all over the world. Europe, nowadays, values strongly the mobility of workers, the movement of know-how and labor force between different countries inside Europe. There are no borders for most of the everyday professions.

Jan 1, 2018

By John Yenter

"Unique blasting problems during reconstruction and expansion of 100 year old buildings toaccommodate gambling. Located on steep mountainous terrain and linked by narrowroadways, the towns of Central City and Black Hawk challenged blasters to exceptionalmeasures in order to control over_break, vibration, public exposure and damage to thecharacter of these historic mining towns. Utilities were also upgraded to fit demands of asmuch as 800% volume change in one year."

Jan 1, 1993

Several surface coal mining operations in North America are attempting to adapt microprocessor-based monitoring equipment as well as programmable logic controllers onto rotary blasthole drills, towards improving overall drill and blast productivity. These Monitoring While Drilling (MUD) systems permit the recording and processing of important drilling parameters such as rotary speed and torque, instantaneous penetration rate and weight on the bit, and enable the operator ultimately to optimize drill and bit performance. MWD systems on production drills in surface coal mines offer the potential to define mine bench geology in detail and in advance of explosives loading. Recent advance s in explosives and initiation technology will require such a detailed knowledge of ground conditions in order to be fully exploited. Additionally, the logic developed from drill monitoring technology will eventually enable full drill automation through feedback and control, once a more complete understanding of the influences of rock mass characteristics on machine performance is achieved.

Jan 1, 1988

By M Oldenburg, P J. Digby, L Nilsson

A constitutive model for the simulation of fracture and fragmentation processes in rapidly loaded rocks is studied. The model was included in a wave propagation finite element code. The results obtained from two different configurations of explosive charge and reflecting surfaces in a plane strain problem were studied. The evolution of the time-dependent fracture pattern is presented.

Jan 1, 1985

By S R. "Bob" Pilshaw

Productivity is the popular "buzz" word that catches the attention of most managers when it is featured in the more popular mining and construction magazines. Engineering Task Forces and teams are formed to take advantage of productivity opportunities in almost all phases of an operation except the drilling and blasting area.

Jan 1, 1988

By Kahmmelly Mathildes Pimenta Coelho, Felipe Dantas, Jaine Ribeiro de Souza, Augusto Ferraz, Carlos Roberto Campos Junior, Davi Bastos Martins de Oliveira

The Carajás Iron Mine, recognized as the largest iron ore province in the world, is notable for its continuous efforts to improve operational efficiency and safety. In response to these objectives, a QA/QC (Quality Assurance and Quality Control) Program was implemented and integrated with Blastscout Probe technology to optimize drilling and blasting processes. The program supports the standardization of operational parameters, the execution of regular audits, and real-time data analysis, facilitating precise and timely adjustments. The implementation led to significant improvements, including an 80% increase in operational compliance, a 49% reduction in drilling depth deviations, and a 30% enhancement in Jaspelite fragmentation. This study presents the methodology employed, the outcomes obtained, and the positive impacts observed in both operational performance and environmental management.

Jan 26, 2026

By Catherine T. Aimone

A series of experiments have been performed to characterize fragmentation and microcracking in quartz monzonite copper porphyry. The flyer plate impact method was used to generate plane shock waves in rock specimens for impact pressures between 1.6 and 7.3 GPa and impact pulse durations between 1.1 and 7.0 µs. The effects of pressures up to 4.8 GPa and pulse duration on fragment size distributions and microcrack densities were studied. The results show that pressures effect particle sizes to a greater extent at higher pulse durations. However, changes in pressure and pulse duration show little influence on the density of microcracks induced during explosive loading. These results indicate that the nucleation and growth of microcracks in rock subjected to shock waves occur uniformly throughout. A substantial decrease in particle sizes for high pulse durations is attributed to more time allowed for microcracks to grow and coalesce, forming individual particles.

Jan 1, 1985

By Peter Moser, A. Gaich, E. Grasedieck Zechmann

In The SMX Blast Controller is a novel tool for precisely controlling the geometry of a blast based on the technology of 3D imaging. It enables to derive precise information about the geometry of the face of a bench in a quarry from a pair of stereoscopic images taken from the bottom level of a bench with a calibrated standard digital camera. Apart from staking out the blast position with delimiters that mark the area to blast and taking then two images (freely), no further actions are required which allows performing the data acquisition without requiring any surveying skills. The 3D image generation and blast planning does not require special computer. It is estimated, that every blast foremen is able to work with the system after a one-day training as the system includes a high grade on automatism. The software package allows the blast foreman to design and stake out a blast, based on provided geometric values, such as burden, side spacing, hole inclination, sub-drilling, row number & distance and drilling pattern. The software connects these values with the 3D information acquired by the digital images. All the drill & blast information can be used also for blast documentation. The SMX Blast Controller overcomes also the problem of doing the back transfer from maps derived by surveying into nature as the resulting 3D image and all the information associated to it (hole position, etc.) can be correlated with the nature by visual comparison and the help of a single reference line, defined by two points. The system is designed to be used also in small to medium quarries. It can help, that the control of the geometry of the bench face and the precise design of the charge of the blast on a borehole per borehole basis will become an accepted daily routine.

Jan 1, 2006

By F. Malek

An extensive blast monitoring program has been carried out to study explosive performance and the effectiveness of blast designs in production blasts in a deep underground mine. Comprehensive monitoring of blasting vibrations through multi-station high-capacity high-frequency accelerometers, and borehole deformation history have been the main tools of such analysis. The mining activity involves relatively unstressed stopes as well as highly stressed stopes. More than 30 production blasts have been monitored, and the respective vibrations from close-range as well as distant seismic stations have been analyzed, and the vibration parameters (amplitude and frequency) have been correlated with explosive charge weight in the holes. It is found that the correlation between blasting rounds and the corresponding vibration amplitudes often have poor correlation for a very significant portion of the blasts. These point to either explosive charge malfunction in those specific blast holes, or inadequate blast design, or the effect of high in-situ stresses, or any combination thereof. This paper analyzes these variables and their effect on the overall blasting operation at the mine.

Jan 1, 2013

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 Charolett Hayes, A. L. Russell, Anthony J. Bednar, Jared Smith, Valentine A. Nzengung, Stephen L. Pilcher

The manufacture of Energetics Materials (EM), including maintenance and demilitarization of munitions causes dangerously high levels of explosives residues to be harbored in building features. The two commonly approved methods of decontaminating energetics contaminated equipment and building features are thermal treatment and steam washing. The current regulatory environment is generally becoming more stringent and unfavorable to thermal and steam decontamination because of their adverse impact on air, soil, and water and their ineffectiveness to completely remove accumulated energetics from foundation cracks, internal and external piping, voids in walls and ventilation systems, and internal cavities of fixed equipment. However, chemical destruction of energetics, especially high explosives, is gaining acceptance as a safer, cost-effective and environmental friendly alternative to thermal and steam decontamination. Organic explosives, including nitramines and nitrate esters are oxidized organic compounds that are susceptible to chemical oxidation and reduction reactions. Under suitable conditions, a chemical reagent consisting of sulfur-based bulk reductants (neutralent) commercialized as MuniRem generates highly reactive free radicals that very rapidly degrade many energetic compounds to innocuous end products while stabilizing metals as the insoluble metal sulfides.

Jan 1, 2016