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By Ewan Selers, Gary Cavanough

Drilling automation technology is well advanced and automated drill rigs are in use at a number of operating mines. This is not the case for the other drill and blast processes due to significant technical challenges to overcome. These challenges, with regard to the current “on bench” practices, include placing the initiators, loading the explosive and connecting up the initiation system. Although difficult, these challenges will be solved with engineering advances.

Jan 1, 2016

By Shazad Hosein, Bill Birch, Catherine Johnson, Toby White, Liam Bermingham

Air overpressure (AOP) from blasting can give rise to a significant number of blasting complaints from residents living adjacent to blasting operations from mines, quarries or civil engineering projects. High amplitudes of AOP are usually associated with the lateral movement of a vertical free face, but it can also be caused by the upward lifting and the venting of gases through the surface of the blast area.

Jan 1, 2018

By John Platt, Mark Stephens

"When blasting is required in critical areas and anticipated shot movement and quick cleanup areessential to the success of the project it is extremely important to use the best technology available to achieve the goals expected by the customer. Wampum Hardware was given such a challenge in 2014-2015 when the PA Turnpike and New Enterprise Stone and Lime hired the company to do presplit blasting along the PA Turnpike. The face height averaged 45 feet (13.72m) and the shots had to be controlled to stop within 60-75 feet (18.29-22.86m) of the face or in this situation before they entered the travel lanes on the PA turnpike. In many if not most blasting environments, it is essential in controlling the movement of a blast, to make certain that the face holes are drilled at exactly the right place, with the proper amount and type of burden in front of and to the sides of the borehole. Profiling is an important first step to insure that the holes are drilled at exactly the right place and showing us the correct amount of burden in front of each and every drill hole."

Jan 1, 2016

By Alastair Torrance

The performance of commercial explosives is clearly influenced by the conditions under which they are used. Mining companies are supplied with Technical Data Sheets which provide details about explosive properties and its suitable application. These are generally produced using laboratory techniques which may not accurately reflect the quality and performance of the product in the field.

Jan 1, 2013

By Kurt Oakes, John Williams

Placer Dome, US operates the Bald Mountain Mine. The Bald Mountain Mine is a surface operation located in remote northwestern White Pine County in east-central Nevada, approximately midway between Elko and Ely. The mine is in the Newark Valley along the southwestern flank of Bald Mountain a part of the Ruby Mountain range, at an approximate elevation of 7,500 ft (2,286 m). The geology at the Bald Mountain Mine is highly altered, both mineralogically, and structurally. Highwall stability and control have long been an issue at the operation, due largely to the varying geologic conditions. In some blasts as many as seven distinct geologic unconformities exist. These unconformities affect both final high wall integrities, as well as blast fragmentation characteristics. A 60 million ton (54.5 million tonnes) layback expansion of the existing “Top Pit” as well as development of a new satellite pit, “Sage Flats”, is being undertaken. Design final highwall pit slopes have been steepened from the traditional 47º to 55º in order to reduce overall ore-to-waste ratios, thereby improving economic viability for the expansion over the 4.5 year life of the project. With the increased usage of electronic detonators throughout the mining industry, mine operations staff, as well as representatives from the mines explosive supplier felt that an evaluation program incorporating electronic detonators would be warranted. The areas of focus for this evaluation would be resultant highwall pre-split integrities, peak particle velocity measurements (both near field and far field), frequency measurements, loader productivity, and visual interpretation of the results. The mine incorporates 25 ft (7.6 m) benches and uses separate trim blasts in conjunction with production blasts in order to reduce blast effects along final highwalls. Hole diameters in production blasts are 7? ” (200 mm). Typical production blast patterns are 18 ft x 18 ft (5.5 m x 5.5 m), drilled in a square pattern configuration. Shot sizes vary greatly, ranging from 200 holes to as many as 800. Bulk low percentage ANFO/emulsion blends are utilized as the redominant blasting agent. Non-electric dual delay detonators (25 ms/500 ms), with non-electric surface delays are the initiation system utilized in production blasts. Typical production blast design

Jan 1, 2004

By M. Syafiq Isnaya, Rahma Norfaeda, Slamet Rachman Jaka

This paper is about project improvement to maximize energy distribution while ensuring beneficial blast results (reduce boulder condition). The main problem is how to manage complex lithology conditions related to detonation propagation in energy distribution control.

Feb 1, 2020

By Robert L. Brooks

Blasting liability problems are frequently compounded by a company's inability to effectively communicate with concerned property owners and the lack of adequate complaint documentation. Often, by the time the insurance carrier becomes involved in a blasting claim, the situation has deteriorated to the point that a solution agreeable to both parties is virtually impossible to reach. The insurance carrier, wishing to minimize their lose potential may decide to pay on a somewhat questionable blasting claim rather than be drawn into lengthy civil proceedings that would ultimately end up in front of a jury with little chance for a successful outcome.

Jan 1, 1992

By Robert B. Hopler

This paper reviews, from the historical standpoint, the development of the commonly-used terms such as "No. 6 and No. 8" with regard to detonator strengths. The origin of the strength terminology is reviewed, and the many methods developed to compare the strength of one detonator to another are described, with the good and bad points of each method outlined. The "miniature cartridge test," very highly regarded by both the U.S. Bureau of Mines and Institute of Makers of Explosives in the 1930's and early 1940's, is described in detail, as is a test developed and used by IRECO.

Jan 1, 1992

By Uli Leiste

Two papers are presented which examine Air Deck Blasting, one from a computational aspect and the other from a shock aspect.

Jan 1, 2016

By Keith Best

It has been said that when a person does something right no one remembers but when they do something wrong no one forgets. This statement, when applied to the explosives industry, has never been truer. Think about it.How many times have you seen a news crew reporting on how well a blaster is doing his/her job? Normally, all you will see is how bad things are going and how much “damage” is being done.

Jan 1, 2008

By G. C. Naveen

Punatsangchu Hydroelectric Project Authority is constructing 1020 MW underground hydroelectric project in Bhutan. The project envisages construction of concrete dam, Desilting Chamber, Head Race Tunnel, Power House Complex and Tail Race Tunnel. Tunneling is one of the major activity in any underground projects as they are driven for multiple activities. By and large the tunnels are a major part of connecting networks from surface to caverns/underground working sites. Many tunnels in hydropower project are part of water conducting systems and one such important tunnel is the Tail Race Tunnel in this project and had to be excavated in thinly foliated rockmass conditions by D&B method. The rockmass is traversed by three to four joint sets and few minor shear seams. Rock Class “Q” values were between III and IV. Tunnel was excavated by full face parallel hole drilling blasting method. The adopted blasting method consisted of drilling 45mm (1.77 inch) diameter holes to a depth of 2m and the drilled holes were charged with 40mm (1.57 inch) diameter cartridge explosives and charges were initiated with half second non electric initiators. The perimeter holes were drilled at closer spacing of 30cm (1 feet) and alternate holes were charged using 32mm (1.23 inch) diameter cartridges explosive. Low dipping foliation joints present in the rockmass tend to slab in crown portion and erratic occurrence of intrusive bodies lead to unpredictable behavior of rock mass posing a major challenge for the safe excavation. Stability was a major issue through controlled blasting under constant supervision too could not limit the overbreak in certain weak rockmass conditions thereby exposing cavities of about 2.5m (8.2 feet). The stabilization of these cavities and handling the overbreak due to rockmass condition was time consuming and warranted additional supports. With systematic measurements and controlled blast designs the Horse Shoe Shaped Tail Race Tunnel of 9.1 m (29.85 feet) diameter and 304m (997.37 feet) length to connect with Downstream Surge Gallery of 314m (1030 feet) length, 18m (59 feet) wide and 58.8m (193 feet) height in thinly foliated and jointed biotite gneiss rockmass was successfully excavated.

By Rajesh Sonkar, Sanjeev Kumar

The deployment of Dragline machines in opencast coal projects involves huge capital expenditure as well as operating costs. The mine operators always endeavor to ensure smooth excavation of material by the Dragline machines while meeting the major objectives of safety, minimal disturbance to environment and optimal operating costs. Optimization of fragmentation through well designed blasts is fundamental in meeting part of the objectives is good fragmentation of rock or mineral proposed to be lifted by the Dragline machine. If the overburden lying over mineral is not properly fragmented, it may result in formation of ‘Toe’ the removal of which is the most arduous task in opencast coal mines. The mine operators always endeavor to achieve best possible results in blasting to ensure smooth operation of the high cost Dragline Machine. However, despite continuous efforts by the blasting engineers involved in bench blasting for the machine, the formation of ‘Toe’ is an ever nagging problem faced in large opencast coal projects eventually reducing the overall operational efficiency of mining.

Jan 1, 2011

By Michael S. Wieland

"This report investigates whether it is tractable and thereupon reasonable to remove the boosterinfluences when ranking the toxic fumes of non-cap-sensitive mining explosives. The hazard potential is represented by relative fume toxicity RFT, the resultant influence computed from a formulated rule with a restricted set (tally) of fume components and multiplying constants. The RFT result is compared to the rule criterion that represents the worst case tolerable toxicity stipulated by regulations or otherwise. The typical nonstoichiometric booster composition can render notable unwanted influence on the RFT ranking results. Historically, the remedy was to shoot the booster separately and reduce the trial concentrations by the relevant subtractions. Unreal negative concentration results were noted on rare occasions, revealing the faulty nature of the reduction procedure. With thermodynamic reaction chemistry codes TDRC, on the other hand, the booster ingredients can be retained in or removed from the reactant tabulation, yielding reduction factors taken as the concentration ratios for the two circumstances. The underlying presumption regarding reduction factors is that the ratios of component concentrations with and without the booster ingredients when resolved theoretically ought to equal those rendered experimentally, when tractable. Upon rearranging the presumed relationship, the unadjusted fume concentrations divided by theoretical reduction factors yield the wanted readjusted fume concentrations, thereby removing the booster influence without generating unreal negative concentrations."

Jan 1, 1999

By Evan Smart, Andrew Palangio, David Klingspor, Blessing Taiwo

This study presents a DMAIC-based approach to optimize blasting performance and achieve crusher-compatible fragmentation at the Walker-Severn Quarry in Ontario, Canada. By applying the Six Sigma DMAIC (Define, Measure, Analyze, Improve, Control) framework, the study aims to enhance the integration between blasting and primary crushing operations. Several representative blasts will be simulated and evaluated using both aerial and terrestrial image analysis technologies to assess fragmentation characteristics. The investigation was guided by quarry-specific Key Performance Indicators (KPIs), ensuring that blast design modifications were both practical and operationally relevant. Through structured analysis and data-driven refinement of blast parameters, the study reveals how this framework was used to address the quarry production demand for increased crusher throughput, and reduced processing costs. The existing quarry blast design was assessed as a baseline and compared against the crusher's inlet requirements and the acceptable fines level specified by the quarry. This evaluation aimed to identify and implement modifications to enhance blast performance. A drone (UAV) was employed to capture post-blast images and monitor blast pile displacement. These UAV images were used to generate an orthomosaic image, which was analyzed to assess fragmentation. The orthomosaic was overlaid onto a GIS platform using a 10m-by-10m grid to evaluate fragmentation distribution across the bench and identify areas requiring optimization. Additionally, drone imagery was utilized to monitor the impact of each blast on the subsequent blast's free face and to assess energy utilization for optimizing front-row holes to achieve improved fragmentation. The outcomes of this research offer a replicable methodology for continuous improvement in quarry blasting practices, with a focus on producing fragmentation that aligns with primary crusher requirements.

Jan 26, 2026

By Tom C. Palangio

Commercially available online particle size analyzers (OPSA) are in their third decade of development (Palangio, T.C., 1985), (Franklin, J. A., Maerz, N.H., 1987), (Maerz, N.H., Franklin, J.A., and Coursen, D.L., 1987). The installed base of operating analyzer numbers is in the hundreds. This paper takes a look at five critically important relationships that users have discovered through the use of OPSA systems. The two key attributes of these systems are: 1) consistency and, 2) historical context compared with traditional practices.

Jan 1, 2016

By J Silva Castro, W C. Wedding, B T. Lusk, J Calnan, E G. Morris

The emergence of electronic detonators for use in production mine blasting has enabled mining professionals to rethink the traditional blast design methodologies that pertain to timing. In many ways, electronic detonators can allow great advances in productivity, cost effectiveness, fragmentation, and safety. This paper reports on an independent study quantifying the accuracy of two electronic and two non-electric systems in which 674 detonators were tested. This research aimed to determine the accuracy of commercially available electronic detonators as compared to non-electric shocktube systems. Each system was tested over the viable ranges of delays available. Statistical models were then applied to quantify the scatter present in each system. Suggestions for the use of electronic detonators are made from the findings of this work. This work was made possible through funding from the United States Department of the Interior Office of Surface Mining Reclamation and Enforcement.

Jan 1, 2012

By Ruilin Yan, Kameron Ray

This paper reports a simple approach to model the waveform change due to travel distances based on the field measurement. A linear interpolation is used to estimate the waveform at a distance from two vibration waveforms recorded at two different distances. The resulted waveforms are compared with actual recorded waveforms at the point in both time and frequency domains. It shows that the proposed method to estimate the waveform change yield reliable results. The advantages of the proposed method are that it does not require assumptions that a transfer function does and that it is based on purely the measured waveforms that are encoded with in-situ rock properties. The method could be more reliable for far field seismic waveforms and could be an approximation for near field waveform estimation.

Jan 1, 2014

By Kevin Phelps, Jason Baird, Philip Mulligan, Dominique Nolan

Determining the transitions from run-up to optimal cut length and optimal cut length to run down, without bias, from the penetration of a linear shaped charge (LSC) is difficult. The stresses applied to the targets during explosive testing can distort the targets in such a manner that determining the true distance of cut, penetration, or fracture can be demanding. Through the course of this research, it was observed that the researchers made many of the errors involved in the collection of data. Among these errors researchers found problems in: determining and fitting the sample to a single plane from which to read measurements, determining where along the path of cut the three phases of penetration transition, and the precision of measurement based on handheld tools and the human eye. This study looks at three methods of recording the data of a series of linear shaped charge tests. The tests resulted in samples which are not ideal for measuring with common laboratory devices like measuring tapes, calipers, or rulers. The first method utilized these common laboratory devices and the difficulties the authors experienced are described in this paper. The second and third methods involve digital photography, image manipulation, and the use of AutoCAD. Methods two and three are then compared to the simple observational method and discussion is made in regards to the precision and accuracy of each method.

Jan 1, 2013

By John Floyd, Maria Rocha, Benjamin Cebrian

Wall control blasting is needed in most metal mining operations in terms of increasing mineral reserves and assuring the safety of the operation. This type of blasting has the goal to achieve a clean, stable rock wall in the shortest distance from a well fragmented, easy to excavate, blasted rock mass. This can be done with a variety of blasting techniques, all of which decrease the explosive energy towards the final wall. Each technique needs to suit the geology: modified production blasting, buffer blasting, pre-split and line drilling of empty holes. Pre-split is the most expensive technique, and allows final steeper bench face angles while modified production blasting is the least expensive but needs wider berms.

Jan 1, 2018

By Damien Bretall, William Fourney

Due to the changing face of warfare there is an ever growing need to protect the underside of combat vehicles from mine blasts. This paper presents a new method to better characterize the pressure profiles experienced by a plate as the blast develops. The explosive deformation of a small-scale plate was recorded using synchronized high-speed digital cameras, and then analyzed using 3D Digital Image Correlation software. Time-varying pressure profiles were input into an axisymmetric FEM simulation by fitting curves to data obtained from tests using Kolsky bars to measure pressures. These were then modified to find possible profiles that produce the measured deformations. It was discovered that the final deformation cannot be determined from only total impulse or peak pressures, and that it is very sensitive to the time and spatial decay of the pressures.

Jan 1, 2009