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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 Ian Bell

This paper investigates fragmentation in an aggregate quarry using the fragmentation-energy fan concept. Six blasts were monitored, located one behind the other in the same quarry area. The rock structure was blocky, the water level and the usage of explosives were variable within and between the blasts. The powder factor above grade was between 0.28 and 0.44 kg/m3 (0.47 and 0.74 lb/yd3). Fragmentation of the plant feed was measured using an online digital image analysis system and three belt scales. The oversize material that was not directly fed to the plant after the blast corresponds to 3‒9.3 % of the total. Data from image analysis was used to build the size distribution in the coarse range (fragments above 120 mm), and the passing fractions at 120 and 25 mm (4.72 and 0.98 in) obtained from belt scales data were used in the range 120‒25 mm (4.72 ‒ 0.98 in) . The non-dimensional percentile sizes between 10 and 90 % for each blast are described through power functions of the powder factor above grade; the model coefficients are statistically significant. From them, using the principles of the fragmentation-energy fan and the Swebrec distribution properties, the fragmentation can be expressed in terms of the powder factor by means of five parameters: the fan focus coordinates and the three parameters of a function of the exponents vs. the percentage passing. The model shows a good capability to describe fragmentation.

Jan 1, 2019

By Jean-Francois Lagueux, Andre Pomerleau

Goldex Mine is an underground mine located near the town of Val-d’Or. Multiple innovations were required to work the mine. Due to its low grade, it was important to develop a bulk mining method to economically extract the ore. The method used is a combination between shrinkage stope and long holes stope methods. This modified method is more than adequate; however, all of the ore body must be liberated in a very short period of time. Therefore, to bring down 23.0 M tonne (25.3 M ton) of ore, large blasts up to 1.8 M tonne (2.0 M ton) are required. The situation is also complicated by the fact that the mine is located in a residential area. No less that 40 homes are built within a 1 km (0.62 mile) radius of the mine site.

Jan 1, 2011

By Dr. Anurag Agrawal, Fathur Rozaq, Nella Lubis, Relinda Sanistya, Herry Saputra, Rudolf Sitorus

In mining operations, basic drone applications such as pre- and post-blast photo comparisons, blast video recordings, and sample-based fragmentation analysis are often used to assess blast performance. However, these methods lack the depth needed for comprehensive evaluations, leading to suboptimal results. This study explores the innovative integration of drone mapping technology with artificial intelligence (AI) at the Martabe Gold Mine in North Sumatra Province, Indonesia, to address these limitations. High-resolution drones and ground control points (GCPs) are utilized to create detailed orthomosaic maps, and advanced AI algorithms are applied to enhance the accuracy of blast performance insights. Field experiments reveal substantial improvements in comprehensive blast performance evaluations through this integrated approach. Enhancements include improved pre- and post-blast evaluations, AI collar detection, fragmentation size measurements, heave muckpile profiles, cast material measurements, floor prediction models, and muck pile topography volume, which is vital for ore tonnage predictions. Notably, this method achieves an average volume accuracy of 1% compared to light detection and ranging (LiDAR) technology. While LiDAR is known for its precision, the drone-based method offers a highly accurate, cost-effective, and user-friendly alternative suitable for mining applications. Despite LiDAR's superior precision, our approach provides a practical solution due to its accessibility and ease of implementation. In conclusion, the integration of advanced drone mapping and AI technologies has the potential to revolutionize blasting operations. By addressing the limitations of previous methods, this approach meets the evolving needs of the mining industry and sets new standards for accuracy and effectiveness in blast performance assessment. The combination of high-spectral drone images and AI-based software analysis demonstrated nearly 99% accuracy in ore tonnage prediction models compared to LiDAR, showcasing its promising capabilities.

Jan 21, 2025

By Douglas R. Burns

In New England, an area of the country where 3 ½" holes are considered large diameter,we are starting to experiment with 5" and 6" holes. The results are excellent in some areas and poor in others. The geology of rock is the major consideration to account for the blasting results.

Jan 1, 1997

By Bill Birch, Toby White, Ian Brown

costs/benefits of electronic detonators and measure their effects on primary crusher productivity. 9 blasts (3 shock tube blasts, 6 electronic blasts). Measured electricity consumption & primary crusher throughput. Change to Electronic Detonators resulted in a 7% reduction in primary electricity costs and a 15% increase in primary crusher productivity.

Feb 1, 2020

By Sayantan Chakraborty, Kaushik Dey, SaKaushik Dey tyabrata Behera

Drilling and blasting is a popular excavation technique in the drift of underground mine. Faster completion of drift reduces the gestation period and thus longer blast pulls are attempted with longer drill holes. This compels the blasters to initiate higher charge quantity with higher confinements and ultimately results into blast-induced cracks beyond the desired periphery line of excavation. Assessment of the extent of these crack networks is difficult and often neglected. Near-field ground vibration models are often used as damage predictors (Dey, 2007, Yang et.al 1993, Holmberg et. Al 1979) but not necessarily deals with the positions of the cracks. Qualitative measurement of actual damage extent often measured using some geophysical tools, namely, P-wave velocity (Tezuka, 1995), seismic imaging (Dey, 2011), bore hole pressure monitoring (Brent and Smith, 1996), electrical resistivity (Grady and Kipp, 1993), GPR (Adams et.al, 1993) etc. Ground Penetrating Radar (GPR) is a similar geo-physical tool, which uses Electro-magnetic (EM) pulse for characterizing the medium. Similar to other geo-physical tools, GPR also comprises of a transmitter and one/multiple receivers to generate the EM pulse and receive the same after reflection/refraction from the medium(s) respectively. After its development in 1970s, GPR gained increased popularity due to its application in many important fields, namely, identification of buried objects, geological characterization, identification of geological disturbances etc. Thus, it is felt that GPR technique can be used to detect the invisible cracks inside the rockmass from the rock surface (wall and roof) itself. Understanding the same, field experimentations are carried out in an underground manganese mine in Central India, which operates on the ‘cut and fill’ method of mining at a depth of around 300m from the surface. Wedge cut blasting is carried out in the horizontal drifts of the mine using suitable blast design. A 1.6 GHz antenna was used for the GPR scanning, in which GPR transmitter transmits signals predominantly of the said frequencies. The signals get reflected back from any type of interfaces between materials in the target area, with different dielectric properties and is received by the receiver part of the ‘trans-receiver’ antenna and memorized in the Data Acquisition Unit (DAU). The data acquired is processed using a software. Ground vibration monitoring of the blasts are also carried out to develop a vibration predictor. The numerical analysis of near-field vibration predictor model results into the estimated vibration levels at the point of identified cracks. Introduction

Jan 1, 2019

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 Tyler Acorn, Paul Worsey, Nathan Rouse

The effect of the hole diameter on vibration attenuation has not been incorporated in most vibration models in the blasting industry. In current vibration models, the charge weight and the distance from the blast are the two primary variables that are addressed. Charge weight is a function of explosive density, charge length, and charge diameter. This geometry-weight can complicate the isolation of the charge diameter variable.

Jan 1, 2013

By Patrick D. McLaughlin, C Fordham

"The project outlined in the accompanying paper was to densify beach sands on the pond side ofa tailings dyke to the strength required for future dyke construction, This was to be achievedthrough the detonation of relatively small explosive charges in the sand to cause settlement intoa denser state."

Jan 1, 1992

By G Mendoza, L Taddei, C Robertson

It is a well-known industry fact that many mine sites around the globe experience blast holes that have elevated temperatures due to reactive ground, geochemical reactions, geomorphic reactions, sub level open fires, etc. It has been reported in many previous industry publications (White, Saputra et al) that elevated blast hole temperatures are a norm at many mine sites and are dealt with on an ongoing basis while the drill and blast process continues under elevated states of alert. The choice of explosives products including the type of detonator, primer, accessory, and bulk product all must be taken into consideration when loading blast holes where there is a known potential for elevated temperature conditions. It should also be noted that these elevated temperatures inside blast holes can be consistent throughout the blast hole length or vary in position within the blast hole depending on the mine conditions mentioned in the opening statement above. The risks associated with the loading of primers and bulk explosives in holes where elevated temperatures are present include: the ejection of the bulk explosives product, deflagration of the explosives during initiation of the blast or premature and uncontrolled initiation of a blast hole(s). This paper describes a unique and novel approach to the active monitoring of the temperature within blast holes with the application of electronic detonators with integrated temperature measuring (ITM) capabilities, deployed and demonstrated at a mine site in Mexico during January 2023 to March 2023. The deployment of ITM capable electronic detonators allows a user to monitor and record the real time temperature at multiple locations (e.g., toe, middle and collar) at each electronic detonator’s position within the blast hole, with the ability to react instantaneously to elevations in temperature reported. The measurement of the temperature can be for a single ITM electronic detonator, or simultaneous for an array of ITM electronic detonators, allowing for the potential for the data to be represented by a time/temperature/hole depth three-dimensional heat map. Changes in temperature at different borehole positions can vary, however, often the collar position is expected to be the most reactive due the combination of bulk explosive product and oxygen exposure, which can be confirmed with the application of the ITM electronic detonators. A mine site’s reaction to a measured elevated temperature within a blast hole can vary depending on the temperature measured and the change in temperature from the last measurement made. The study was found to produce real-time in-hole temperature information which was previously unobtainable without the introduction of another device. New and adaptive elevated temperature hole policies can be created and adapted proactively as real time information is received, leading to a safer mining operation.

Jan 21, 2025

By R. Jacob Cefalo, Miguel Valenzuela

The modern drill and blast engineer operates in an environment often rich with data from drilling data and blast designs vs. actuals to fragmentation distributions and vibration records. Despite this abundance, much of the information generated remains underutilized, often collected as a matter of routine rather than for a means to an end. This paper explores how artificial intelligence (AI) can bridge that gap, transforming raw operational information into actionable insights that lead to more consistent and optimized blasting outcomes. Through AI-driven analysis of drilling logs, burden and spacing measurements in design vs. actual, fragmentation distributions, and vibration records, we can identify hidden patterns and correlations that traditional analytics overlook or that we may not be aware of. These insights enable engineers to proactively adjust designs and loading strategies, ultimately improving performance aspects such as improving fragmentation, minimizing ground vibration, and lowering overall operational costs. The paper examines the industry's reliance on lagging indicators, such as post-blast fragmentation surveys or actual powder factors, and suggests the need to shift toward leading indicators like real-time drill data monitoring and predictive fragmentation modeling. Utilizing AI to forecast outcomes before a blast is carried out allows engineers to take corrective actions early in the process, thereby creating a feedback loop that continuously improves performance. This integration of AI into drilling and blasting practices marks a pivotal opportunity for the explosives engineering field to evolve from reactive to predictive methodologies unlocking a new level of operational intelligence and value creation.

Jan 26, 2026

By Jose Luis Pineda Villarreal

New technologies emerge every day with practical applications for open pit mining. For every operation, managers need to understand the best way to increase efficiency in drilling, blasting, fragmentation and hauling routes.

Jan 1, 2018

By Keith Maki

This paper details a simple substitution of precise electronic timing in the holes for standard pyrotechnic delays. In addition, we wanted to use two electronics in bottom and top to test the colliding shock wave theory. It also discusses the difficult loading conditions on the Iron Range of Northern Minnesota. No preliminary analysis (Signature Hole waveform analysis) was done to determine the most favorable blast timing for fragmentation increase or vibration reduction.

Jan 1, 2007

By M. Y. Wong

Electronic detonators have been used on a trial basis for over a decade, and found more recent application in production blasting as well. The relative merits of these detonators and their applicability are outlined through examples from actual blasting operations. They offer unprecedented flexibility in the design of mass blasts and in control of vibration and blast-induced damage. However, the drive towards replacing the pyrotechnic detonators by electronic ones in general could prove to be counter productive without a re-examination of prevailing blasting practices. In fact, such an approach tends to blur the tremendous potential of the electronic detonators in redefining many standard blast designs and practices.

Jan 1, 2004

By Erik Nygaard, Klaus Voges

ANFO is the most used industrial blasting agent in the world, and is often used as a reference for comparison of other explosives. It is known to work very well under dry conditions in large borehole diameters, whilst in small borehole diameters increasing amounts of toxic fumes (CO, NO and NOz) can be formed. In underground blasting, problems can also occur with reduced visibility caused by unreacted ammonium nitrate and overall composition of the detonation fumes. ANFO is made by mixing Ammonium Nitrate Porous Prills (AN-PP) and fuel oil. We have measured velocity of detonation (VOD), toxic fumes and visibility after blasting of ANFO in 54x2 mm steel tubes, and the differences are remarkable: By using an AN-PP grade developed for underground blasting and small diameters, the following can be obtained:

Jan 1, 2001

By Robert C. Friend

On-the-job and "hands-on" training programs which attempt to train newcomers to blasting with instructors whose only qualification is their experience can easily miss the boat. Organized training programs which utilize competent instructors and a well developed format are necessary if we wish to provide a meaningful program of instruction, But, let's not go overboard and attempt to provide a level of training which goes far beyond the scope of the worker's duties and responsibilities, and "need to know",

Jan 1, 1980

By Robert B. Hopler

Reefs, exposed rocks, and fast currents made the Hell Gate section of New York's East River a treacherous passage ever since man attempted to sail through the area. As the harbor's importance grew, attempts to improve the channel were made, starting in 1851. This paper discusses the first major organized effort to clear the area, which began in 1869 and culminated in a single large blast in September 1876.

Jan 1, 1981

By D. Lee Petersen, Travis Davidsavor

The 2003-2004 expansion of a Duluth medical center required rock blasting adjacent to the existing structures, a Mn/DOT retaining wall and other urban structures. This case history describes the methods of a blast damage assessment, based on blast parameters, excavation locations, and critical vibration receptors (including surgical suites, a linear accelerator and a major retaining wall). The assessment concluded that blast vibrations could be controlled, by limiting charge weight, to eliminate impact at the critical receptors. Prior to construction, we conducted preconstruction surveys on structures susceptible to vibration damage. During construction, we reviewed submittals, observed test blasts, reviewed blasting logs and monitored blasting vibrations. Up to 13 seismographs were used simultaneously. Close coordination with medical center operations personnel was necessary to prevent impacts to critical medical procedures. Measured vibrations were clustered around the predicted values, and attenuated at the predicted rate. High-frequency blast induced ground vibrations induced low-frequency vibration of an adjacent MnDOT retaining wall. Medical center structures were observed to significantly attenuate the ground-borne vibrations. This paper was first published in the Proceedings of the 56th Annual Geotechnical Engineering Conference, 2008, at the University of Minnesota.

Jan 1, 2010

By Y Nagendra, A. Ravi Kumar

A breakwater is a construction for protecting the marine structures like port, harbor, or anchorage-basin and berthed marine vessels from the destructive influence of the sea waves. The breakwater is constructed by using geologically competent, heavy, massive rock like granite, basalt etc having physical and mechanical properties within the limits specified by the designers. The construction requires boulders in varying sizes ranging from 0.5 kg to 20,000 kg. The stones from 0.5 to 1000 kg are called as core fill and boulders greater than 1000 kg are termed as armor blocks. These armor blocks cover and protect the core fill and prevent it from escaping. The requirement of armor blocks ranges between 25 to 35 %. The rest is core fill. However, the actual requirement depends on the breakwater design. In this context, the task of the mining engineer is to economically produce armor blocks and core from the designated quarry in right proportion with minimal losses. The whole bunch of engineering ingenuities should be put forth for obtaining the required armor blocks. The armor block production from any blast depends chiefly on geological conditions, bench dimensions and blast design. This paper is an attempt to bring out the various parameters affecting the performance of the blasting for armor block production using a case study.

Jan 1, 2005