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By Robert Hopler

HUDSON MAXIM A Noted Inventor of High Explosives ALTHOUGH the subject of the present sketch has been a tireless worker in many fields of activity, his name is best known in connection with his work in the development of high explosives and their application to modern ordnance

Jan 1, 2012

By Jack Eloranta

This paper compares energy requirements for blasting, crushing and grinding. By tracking electrical consumption for various powder factors, a general trend has appeared. This study involves over 100 million tons of ore and powder factors ranging from .5 lbs/LT to .8 lbs/LT. Actual energy usage is compared to predicted energy based on the Bond equation.

Jan 1, 1997

By Thomas Barkley

Mining tradition holds that a parallel round underground can not be any deeper than it’s smallest face dimension. ln other words, a mine using a 12’ (3.7 m) high by 24’ (7.3 m) wide room and pillar mine, the deepest pull that can be achieved is plus or minus 12’ (3.7 m). After experience with decking of rounds in a 12’ (3.7 m) diameter shaft to achieve more than 12’ (3.7 m) advance per round, the concept of deepening the pull on horizontal parallel rounds seemed to be a feasible concept. Tests were conducted in a conventional room and pillar metal mine with a round size of 12’ (3.7 m) high by 24’(7.3 m) wide. Standard rounds were drilled with a 16’ (4.9 m) steel as parallel rounds to an average depth of 14.5’ (4.4 m). The average depth of pull on these rounds was about 13’ (4.0 m). Using the available drilling equipment, 20’ (6.1 m) drill steel was used to drill holes to an average depth of 18’ (5.5 m). Five rounds were drilled and shot with a resulting aven$e pull of 16.2’ (4.9 m) or 90 % of drilled depth. Rounds were designed with decked bum cuts to maximize depth of pull in the cut area An innovative method of de&mining drilling accuraq was used to estimate it’s effect on depth of pull in the rounds. This method used a standard automatic 35-mm camera and scaling to determine the average drill deviation for many of the holes in the rounds.

Jan 1, 2000

By Dae-Woo Kang, Sang-Wook Kim, Shin Lee

The Air-tubes blasting method is provided in which a series of aligned boreholes are charged with explosive s and air tubes in a predetermined blasting pattern. The air tube is composed of cylindrical flexible tubes which have a predetermined width and length to be fit with the site boreholes. Within a preferred formation, each borehole is charged with the explo sives and detonators with an air tube installed just above the explosives. Stemming materials are filled above the air tubes. At the limestone mine of Sung-Shin Cement Co., in South Korea, these blasting tests were performed by a diameter 102 millimeter and 15 m long boreholes with the charging length of explosives was 8m to 10 m by the total weight of explosive 40 to 50 kg with 3m to 6m air tube which has a 76 mm diameter, and 1m to 3m stemming cover. Blasting results showed the about 10% to 30% explosives savings available and especially, the about 20% to 50% reduction of ground vibration with the low noise measures around 2dB to 5dB by this new blasting method which was compared with the conventional blasting methods. The explosives and air tubes may be alternately charged along the boreholes. The use of air tubes which were charged above an explosive layer allow to form the quantitative air decking in every blast hole. Therefore, the Air-deck effect can be easily obtained through this blasting method, and also easy to increase the fragmentation rate resulting in the more suitable mucking procedures at the working site with the minimum usages of explosives for the better economic operations in mine quarries.

Jan 1, 2005

By Ricardo Dr. Chavez, Mathieu Lachamp, Rob Dr. Farnfield

Pueblo Viejo is an open pit gold mine in the Dominican Republic which is always looking forward to implement the newest technology in the industry to improve all processes. Focusing on one of the pillars of the department and our company, digitalization, we’ve been looking for the technologies that allow us the automation of data generation, supervision and process innovation. That’s where a new Drill and Blast software takes place, helping to integrate the process from the beginning to end, right after the pattern is designed until it’s blasted, allowing us to track results like vibration, fragmentation, performance, cost and inventory of each blast in a single platform. The software helps engineers to generate back analysis by blast, bench, pit, month and many other ways, in a timely friendly manner. Therefore, we can catch business opportunities and improvement for the drilling and blasting process.

Jan 1, 2019

By Alastair Torrance, Italo Onederra, Do Sun Kim, Kush Patel, Gary Cavanough

Reactivity of ammonium nitrate-based explosives is associated with the presence of sulphide in the ground reacting with explosive products and in some instances causing spontaneous reactions which can lead to detonation. This paper explains the mechanism of these reactions, the potential cause of spontaneous detonation and how inhibited explosives prevent the reaction

Jan 1, 2019

By Italo Onederra, Miguel Araos

Most of the current explosives for mining blasting activities rely on voids to become sensitive to initiation, then detonating and finally, sustaining that detonation. The use of voids is known as hot spot sensitisation. Various forms of voids serve as hot spots – gas bubbles (predominantly in bulk explosives), glass (or plastic microballoons, for packaged products), or expanded polystyrene (bulk explosives). Gas bubble sensitisation uses the decomposition of sodium nitrite to produce nitrogen gas bubbles, which are dispersed throughout the bulk explosion. These gas bubbles, when hit by a shock wave (such as from a booster), compress and heat up, subsequently decomposing the explosive and releasing energy to sustain the detonation. It has been suggested that the use of different types of gases to create voids in non-ideal explosives could offer some alternatives to the sensitisation process, which could be reflected in the change of the detonation properties of the explosive. The reason would be that each gas has a different ratio of specific heats (=/), and when these gas bubbles are compressed, they will heat up to different temperature, affecting the decomposition of the explosive and thus, the VOD.

Jan 26, 2026

By Pierre De Pasquale, Gilles Jauffret, Ricardo Chavez

"When blasting in quarries or mines, the main source of inconsistent results is directly related to thenon-homogeneous energy distribution through the rock-mass volume. This variation has differentorigins: drilling deviations, geometry differences from one borehole to another (burden, spacing ...),and inherent geological conditions."

Jan 1, 2016

By Pedro C. Carneiro, Luiz G. I. Maciel

"This article presents data of advance and excavation rates in tunnelling works, and how theseactivities interact with the duration and cost of a contract. These key parameters, after analysis andsynthesis, will be used in coming works to ensure the evolution and adaptation of the method created by the Norwegian University of Science and Technology - the NTNU Method - to Brazilianconditions, which will be reflected in the duration and cost of underground drill and blast tunnellingworks."

Jan 1, 2016

By Jack Eloranta

"Unwanted, dynamic interaction of adjacent blastholes is a well-recognized phenomenon. Timingschemes and products are selected to minimize adverse effects. Large diameter, surface blasting is less prone to dead pressing and other disruptions which commonly plague underground and construction blasters. However, several lines of evidence suggest that fragmentation may be compromised as a result of powder column disruption in large diameter shooting as well."

Jan 1, 2016

By Ismael Gottreux Vollet, Carlos A. Muñoz Lira, Alejandro Ferrada Vergara

Currently, underground mining of deeper massive deposits with lower grades, harder rock conditions in high strength environments, entails difficulties in caving, fragmentation and seismicity of the ore body. So far, the use of Pre-Conditioning (PC) with Hydraulic Fracturing (HF) has shown positive results in terms of seismic response and caving ability, while preconditioning combined with explosives aims to weaken the rock mass, causing an additional effect on fragmentation.

Jan 1, 2016

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

In open-pit mining operations, the presence of remnants from past underground labors represents a significant operational challenge, especially if they are in the surroundings of high-grade zones. The existence of uncrushable elements, such as metallic support fragments of abandoned equipment, can trigger critical operational issues if they reach conveyor belts systems or primary crushers, jeopardizing the mine to plant operational continuity. These kinds of incidents lead to expensive unplanned shutdowns, the increasing of corrective maintenance events costs, and risk to meeting expected production results. This work demonstrates the application of a three-dimensional numerical modeling tool for simulating rock displacement post-blasting (by integrating key design parameters, such as blast pattern design, detonating times, charge distribution and pre and post blast surveying). The study was conducted at Andina Mine, operated by Codelco, Chile, and enabled the identification and zoning of areas with potential presence of underground hazards in displaced rock mass, using historical data from previous workings and geotechnical mapping. The displacement results were compared to the actual post-blast surveying, ensuring an acceptability level above 80%, considering both fully confined (bank opening) and free-face blasts. Additionally, this approach allows the determination of an optimal safety offset, initially set at 10 meters and currently under validation for potential reduction. The results supported the determination of safe extraction zones and the design of excavation, loading, and haulage strategies from mine to plant or stockpile, ensuring 100% reliability in the segregation of high risk materials. Implementing displacement simulations underscores their relevance in operational risk prevention and mitigation, adding value to short-term mine planning and strengthening the safety, efficiency and profitability of the open-pit mining production process.

Jan 26, 2026

By Michael Louis, Charles Dowding

Concern over construction vibration-induced cracking has led to development of a new approach to vibration monitoring called autonomous crack measurement (ACM) and illustrated in Figure 1. This paper describes the concept as well as sensor performance in the first test house fitted an ACM system. Response of three cracks in this concrete masonry unit (CMU) house was measured as part of the system verification. ACM employs a single sensor that measures both weather-induced micrometer changes in crack width and those produced by habitation and ground motioninduced vibration. This comparison is displayed in real time via the Internet without human interaction. Graphic display through the Internet provides a new pathway for communication with the public. Such visual comparison of changes in crack width provides a simple alternative to the present system of comparison of measured and allowable vibration time histories. Measurements reported herein show that weatherinduced response of cracks is greater than that caused by presently allowable construction-induced vibration.

Jan 1, 2003

By Tyler Acorn, Tristan Worsey

A dozer operator at a surface gold mine accidentally drove a D10 off the side of a highwall. The blade of the dozer caught on the lip of a catch bench 60 ft. (18.3 m), down stopping its descent. The operator scrambled to safety in fear that the dozer would not hold.

Jan 1, 2014

By Henry P. Jr Van Ormer

During any blast hole operation the first choice to be made is hole size - it seems simple, just calculate all the factors, spacing, burden, depth, rock characteristics, powder factor, etc. and you have it - Hole Size. But we all know that it is not that easy - the "hole size" is part of a system and many other situations can have great impact on the optimum production Blast Hole Size - such as crusher characteristics, hauling capability, mucking capability and - Drilling Capability!

Jan 1, 1983

By Michael Wieland

The thrust of this report is to overcome some of the technical deficiency in the scientific methodology that correlates the work output during a charge explosion to the resulting toxic fumes. Thermodynamic work-principle models yield (undissipated) shock and heave results for shooting underwater and in rock stratum with related toxic fumes. Underwater circumstances yield reliable test data for the work process, though questionable or no fume results. Work-output measurements in rock shots remain difficult if not intractable, though some fume reports exist. Underground tests with thick-wall metal pipe bombs yield consistent toxic fumes trapped within the test chamber. The work output, rendered as fragment kinetic energy, can be inferred from the well-tested theory of R. W. Gurney, originally designed for military ordinance. Therefore a work-principle model for cylindrical pipe bombs was developed to predict fragmentation work output and reaction-zone fumes, permitting the double comparisons to reported and inferred results.

Jan 1, 2010

By Robert Hopler

209. Nitro-glycerine is produced by the action of nitric and sulphuric acids on glycerine, and is a heavy liquid of oily appearance, of specific gravity about 1•6, varying from colourless when quite pure to a yellow or brownish yellow. It is of a very sweet taste, and without odour, and is an active poison. Mere handling of it will in most persons induce sickness and headache. It explodes when heated to about 360° F. or from shock, but in small quantities it ignites and burns with some difficulty by the mere contact of flame.

Jan 1, 2011

By Vitor Fonseca de Barcelos, Jair Carlos Koppe

Our society is experiencing a digital revolution. Technology is demonstrating its significant potential for mining industry. In this paper are presented the measured and estimated impacts of applying new technologies on blasting operations in a copper mine.

Feb 1, 2020

By James Rowland, Richard Mainiero

When most people think of explosives transport they think of a hazardous operation. We all know that we aren’t allowed to transport explosives through tunnels and are discouraged from traveling through heavily populated areas. Popular opinion suggests that explosives transport is a very risky operation. The authors decided to look into this a little more thoroughly and found just the opposite to be true.

Jan 1, 2008

By Bjorn Engsbraten

Explosive charges have been fired under defined conditions in a closed tunnel. The explosives have either been detonated in a steel tube or a single borehole. In the latter case dimensions, -loading density and confinement have been chosen to correspond to common practice.

Jan 1, 1980