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By Michael Burrell

This project involved the protection of an historic landfill located on the site. Construction blasting was for a permanent access road to carry traffic to and from a new metal processing plant being constructed nearby. The landfill contained materials disposed of during the closure of a Phosphorus plant that had previously occupied a portion of this site.

Jan 1, 2012

By Gerard McAlinden, Daniel Frost, Patrick McAlinden, James McAlinden

In an effort to recover Polychlorinated biphenyls (PCB’s) that had leached into bedrock below the Hudson River in Upstate New York, a shaft and tunnel complex was designed that would allow installation of inclined and vertical wells into the zones of contamination to recover PCB’s by gravity. A joint venture of Merco Inc., of Lebanon, NJ, and Obayashi Corporation, of San Francisco, CA, was awarded the contract for constructing the first Tunnel Drain Collection System in the world. Conventional drill and blast techniques were the most economical method to construct the project but due to the presence of PCB’s and community concerns, innovative drill and blast practices were needed.

Jan 1, 2010

By Sérgio Augusto Ferreira, Alan Gerson Diaz Butron, Carlos E. Arroyo, Marcus Neves, Jorhs Enrique Casimiro Huayhua, Dieggo Santos, Eventomar Junior

The presence of natural underground cavities is normally a characteristic of iron ore deposits, specifically in tropical deposits. Brazil and the United States are the only countries that have a legislation to protect these structures, but in Brazil this legislation is very specific for the existing cavities in the federal territory. These cavities are classified by their level of relevance as high, medium, and low. From this perspective, its preservation becomes mandatory, especially, for those of high relevance in order to protect the species (flora and fauna) that live in them. When these structures are within the production phases, it becomes a challenge to exploit these reserves with the use of commercial explosives, since these structures condition and may restrict the use and amount of explosive charge. This paper presents the methodology of controlled blasting associated with predictability via realistic simulation in production polygons, applied in a Brazilian iron ore mine where there is a presence of high relevance natural cavities with restrictions in relation to the limits of Peak Particle Velocity (PPV), which is product of detonation.

Feb 6, 2023

By Peter Moser, Michael Messner, Florian Bauer

The existence of ammonia in underground blasting fumes was frequently measured in various field tests (6, 7). Ammonia in fumes with a TLV (threshold limit value) of around 30 ppm (slightly different in various countries) is a toxic gas but not considered to be a high risk for the underground work force as ammonia smells very itching and is extremely annoying. This might be the reason why ammonia is hardly measured in routine underground blasting fumes control. Another reason for the lacking measurement might be the circumstance that ammonia is a very reactive gas and the ammonia sensors available on the market are very cross sensitive to other gases like carbon monoxide. Nevertheless, especially since the introduction of bulk emulsion explosives in underground blasting, complaints from miners about ammonia in the blasting fumes increased. Research work by various institutions [8] around the world relates the ammonia in the fumes back to various mechanisms. Amongst others these comprise: a) non ideal (low temperature) detonation of explosives, with NH3 in the reaction products; b) reaction between rock and non detonated bulk explosives (especially when the rock is of a basic nature (high pH value); c) reaction between shotcrete and non detonated bulk explosives. Numerous blasting tests in an experimental underground set up have been made in order to check these hypotheses for ammonia origin in blasting fumes. None of them has been found to be responsible for sometimes high concentrations of ammonia in the fumes. The major reason for ammonia concentration in blasting fumes has been found in mine water of a high pH value (either natural or from using shotcrete). The mechanism identified is as follows: the moment a non detonated ammonium nitrate bearing explosive comes in contact with mine water of a high pH value, ammonia is formed immediately. The source for the undetonated explosive is twofold: firstly there is a certain spillage of explosives when the holes are charged (especially when using bulk products) and secondly not the entire explosives detonate completely. These undetonated remaining of the explosives end up in the muck pile after blasting. In case there is water of a high pH value the reaction between the explosives and the water starts immediately. This explains also the observation why ammonia can be measured in the blasting fumes quite a long time after the blast. The majority of the ammonia is not formed during the detonation; it is formed inside the muck pile even a considerable long time after the blast.

Jan 1, 2010

By Paulo Couceiro, Manuel Lopez Cano

"The Panama Canal is one of the most important engineering projects of the modern era and plays astrategic role in the global economy and international maritime trade since its inauguration in 1914. Now, a little more than one century later, the final phase of its expansion program, the largest infrastructure works undertaken since its inauguration, has concluded. This expansion program has created a new lane of traffic along the Canal with the construction of a new set of locks – one on the Pacific side and another one on the Atlantic side -, increasing the Canal’s capacity and its impact on the world’s economy even more."

Jan 1, 2017

By Andrew Palangio, Blessing Taiwo

Understanding rock mass structural features is essential for optimizing blast design, highwall control, and evaluating post-blast performance in both surface and underground mining operations. This paper presents a comprehensive methodology utilizing image-based structural mapping to accurately characterize geological discontinuities including joints, faults, and lineations captured from both terrestrial and aerial imagery at varying scales. Key structural parameters such as joint orientation, spacing, and apparent in-situ block size are extracted to understand rock mass classification and enhance blast design inputs with greater geotechnical precision. The study introduces a significant enhancement to the existing discontinuity assessment algorithm by integrating a deep learning-assisted detection process. This improvement enables more accurate, quantitative and consistent identification of pre-existing cracks and surface features across complex bench free faces. The enhanced system facilitates better evaluation of how structural features influence blast fragmentation, energy distribution, and slope stability. A case study from a limestone quarry illustrates the use of a derived comminution factor based on the relationship between joint-controlled pre-blast block sizes and post-blast fragmentation to evaluate blast performance and optimize future design strategies. The results highlight the value of structural analysis in reducing overbreak, minimizing underbreak, and improving fragmentation predictability. This paper emphasizes the importance of integrating structural assessments into the blasting workflow to enable a more data-driven, geotechnically informed, and performance-optimized approach to modern blast design and evaluation.

Jan 26, 2026

By Julijan Bratun, Joze Kortnik

Production of technical stone is an important economic branch in Slovenia. In 2009, we had 95 dolomite quarries, 27 limestone and 6 silicates quarries, according to the Ministry of Economic Affairs. Together they produced nearly 15 million tons of aggregates. The production in quarries is mostly performed with drilling and blasting method and only a minor part with other method like mechanical mining method.

Jan 1, 2011

By John A. Davis, David W. Brunton

(Excerpts, pp 157-160) The usual means of firing blasting charges, especially in tunnels and adits in the Western States, is by the use of a safety fuse. The term safety fuse originated from the fact that when properly used under working conditions this fuse burns at a uniform rate and does not flash or explode, as was often the case with the means employed for igniting blasting charges previous to its invention; but the term is somewhat misleading, because the fuse is not, nor has it ever seriously been claimed to be, safe for use in gaseous coal mines. The fuse used for tunnel work is composed of a core of gunpowder surrounded by various layers of waterproofing material.

Jan 1, 2015

By H. S. Venkatesh, G. Gopinath, R. Balachander, 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.

Feb 1, 2020

By A T. Spathis, M G. Wheatly

Some preliminary dynamic pressure data were obtained from several charges detonated in a tunnel situated in massive granite rock. The context of the work is the potential for desensitisation of explosives, failure of detonators, and sympathetic detonation due to the close proximity of inter-hole and inter-deck explosive charges to each other. Dynamic pressures were measured using piezoelectric gauges in water-filled 45 mm diameter holes adjacent to the charges. Some of the first arrival peak pressures were noisy, and although not fully resolved, may be due to reflections and the physical arrangement of the transducers and their size with respect to the monitoring holes. The estimated peak pressures were between 0.1 to 8.7 MPa at approximate distances of 2.8 to 0.8 m, respectively. Further work is planned with gauges that are disposable, have a higher pressure range, and can be used within a few borehole diameters rather than the piezoelectric gauges used in the present work.

Jan 1, 2016

By Tyler Acorn

In December of 2009 an estimated one million ton slope failure activated a 10 million ton mass impacting use of the main ramp system in the Newmont Gold Quarry pit. The failure left behind a 400 foot (122 meters), vertical to sub vertical scarp feature and shut down production in the lower benches of the pit.

Jan 1, 2011

By B. M. P. Pingua, M. Nabiullah

Number of mine accidents occurred in Indian surface mines are due to poor quality of explosives and blasting accessories. Amlori open cast project is one of the major coal producing projects in India. Standard drilling and blasting parameters are used to achieve desired productivity of the mine. 150 and 260 mm diameter blast holes are used for blasting in coal and overburden benches. Most of shovel benches are 12 to 16 m in height and dragline benches vary from 25 to 30 m. High-energy bulk emulsions are used for blasting. The cup density and velocity of detonation of bulk emulsion explosives are 1100 to 1200 kg/m3 and 3.8 to 4.5 km/s respectively. An incident occurred on fire bench of Amlori open cast mines during mucking of blasted muck.

Jan 1, 2008

By Ron J. Elliott, David G. Otto

This project involved deep blast densification of recent volcanic avalanche debris deposits consisting of a 43 meter thickness of loose clean to slightly silty sand, gravel, cobbles and boulders deposited as a result of the 1980 eruption of Mt. St. Helens, Washington, U.S.A. This project was carried out to enhance the resistance to liquefaction or dynamic settlement of soil deposits under the bridge abutments for construction of the 59.4 meter long South Coldwater Creek Bridge. As this bridge is located close to the Mt. St. Helens fault, it will in all likelihood be subject to earthquakes in the order of 6.5 with expected accelerations of 0.55g. Without soil densification, the bridge would suffer severe structural damage in the event of a significant earthquake.

Jan 1, 1994

By David Cheung, S. Paul Singh

"The characteristics of a blasted muck pile can have a significant effect on the productivity and economyof loading and hauling operations. Poorly fragmented and tight muck piles, caused by insufficientdisplacement of the broken rock, lead to higher digging and hauling costs. Therefore muck pile must be tailored to suit the loading and hauling equipment. In order to achieve this objective, it is imperative to understand the relevant muck pile characteristics and factors governing them. In general, muck pile characteristics are governed by the blast design parameters, rock mass geology, explosive characteristics and post-blasting requirements."

Jan 1, 2017

By N Gkikizas-Lampropoulis

Selection of delay times to optimize fragmentation has been a controversial topic among researchers and blasting practitioners. This paper interprets previous experimental information on the effect of delay on fragmentation with the aid of some new experimental observations of the time of detachment of the free face of the blast as well as results of numerical modelling. It was shown that detachment of the burden occurs at delays shorter than the one which produced optimum fragmentation in the experiments, suggesting some fragmentation improvement due to gas action. In addition, at the spacing to burden ratio of the experiments, the damage zone from an earlier detonating charge extends the distance to the neighboring charge, essentially affecting the burden of some of the holes of the blast, at detonation time. Computer modelling demonstrated that increased spacing results is less overlap of stress induced damage zones meaning that there is less influence of delay on stress wave induced fragmentation. It was also shown that simultaneous initiation results in less back break, while increased back break may result even with short delay times.

Jan 1, 2016

By Sven-Erik Johansson, Gosta Rundqvist, Donald Jonson

In Stockholm a new road traffic system called Södra Länken (Southern Link) will be in operation in late 2004. The total length of the road system is 6 kilometres of which 4,5 kilometres run through tunnels under suburbs immediately south of Stockholm inner City. The new traffic tunnels together with existing Metro tunnels, which mostly are in rock, will be the determining factor for blast design for many projects in the future. To set reasonable and safe permitted vibration levels the Swedish National Road Administration, Stockholm Region and Stockholm Transport Rail System have together financed a project to determine guide levels for blast-induced vibrations in traffic tunnels in rock. The purpose of the project has been to establish guide levels that are appropriate for different types of rock tunnels.

Jan 1, 2004

By Regina Rocha, Miguel Humpire

One of the challenges within unitary mining operations is blasting, which has a significant downstream impact on the following processes, which is why mining companies ensure the results of the blasting process through joint work with explosives specialists’ companies.

Feb 6, 2023

By Orica Peru, Pedro Lozada

Proper management of exclusion zones in blasting operations is essential to ensure safety without compromising operational efficiency. In Peru, mining regulations establish minimum exclusion distances specifically for personnel (500-meter radius / 1,640 feet), but do not define clear technical criteria for equipment. As a result, conservative distances such as 200 meters (656 feet) are often applied, negatively impacting productivity. This study proposes a technical-scientific methodology to reduce equipment exclusion zones, based on the use of advanced technologies such as drones, high-resolution cameras, and specialized software tools. The solutions used allow video recordings of blasts to be transformed into dynamic data through artificial intelligence and computer vision, as well as execute probabilistic simulations of the flyrock phenomenon using Monte Carlo algorithms and physical models calibrated to real operating conditions. Technological integration enabled the simulation of real operational scenarios, considering variations in critical blasting parameters that directly affect flyrock generation, such as drill diameter, explosive density, linear charge, and stemming height. Additionally, the Terrock methodology was incorporated, allowing the behavior of the rock mass to be included as a variable in risk assessment, improving analysis accuracy under different rock hardness conditions. The methodology was applied in four phases: diagnosis of the current design (15 blasts), modeling, validation of the calibrated model (6 blasts), and subsequent operational implementation. As a result, it was determined that the exclusion radius can be safely reduced from 656 to 492 feet (200 to 150 meters), maintaining as the main restriction the use of stemming lengths greater than 5.0 m. This optimization has the potential to generate tangible benefits, with estimated monthly savings exceeding USD 50,000, associated with reduced evacuation times, lower fuel consumption, less equipment wear, and increased productivity in drilling and hauling activities. The comprehensive approach presented here highlights the transformative potential of digital technologies applied to blast management, contributing to safer and more efficient mining operations.

Jan 26, 2026

By Eduardo Lozano, Vilem Petr

The use of explosives bring countless benefits to our everyday lives in areas such as mining, oil and gas exploration, demolition or avalanche control. However, because of the potential destructive power of explosives, strict safety procedures must be an integral part of any explosives operation. The goal of this paper is to provide a solution against the hazards which unfortunately accompany the use of explosives. For this reason, a blast shield is specifically designed and tested for protecting personnel against these unpredictable effects. This document will develop a complete analysis answering the following questions: what are the potential hazards from an air blast; what are their effects; and how can we be protected against them. In order to answer these questions, theoretical, analytical, and numerical calculations are performed. Finally, a full blast shield prototype is tested under blasting conditions proving its effectiveness as a safety device while explosives are used.

Jan 1, 2015

By Sami Kara, Yunseok Park, Seung-Joong Lee, Namsun Hwang, Michael Laing

This study conducts a comparative analysis of construction efficiency. In the first part we compared electronic and non-electric initiation systems, focusing on tunnel contour holes. Field blasting operations were executed across a variety of delays to identify the optimal delay time. This delay for the in-situ rock mass was determined through regression analysis of blasting vibration in contour holes and for overbreak/underbreak. The blasting results with the electronic initiation system using the obtained optimal delay, applied to contour holes, were compared with the results of the non-electric initiation system. The overbreak and underbreak decreased by an average of 2.7 cm and 5.8 cm respectively, by using the electronic initiation system. Moreover, the vibration reduction rate in contour holes region was reduced by 11.9% based on the blasting vibration estimation equation proposed by the Ministry of Land, Infrastructure, and Transport (MOLIT). Underground construction projects have become increasing popular as cities grow in both size and density. This growth severely limits the amount of useable space for new project on the surface, resulting in the decision to build them underground. This new policy however brings into focus the challenge of managing and reducing blasting related vibration due to the proximity of these projects to sensitive structures, utilities and foundations often present in urban environments. For this purpose, we have been required to manage the vibration by reducing the quantity of explosives used per round. Inspired by surface blasting techniques, we applied a decking mode to address and work around this challenge. We present in this paper the first attempt to blast a tunnel face using a decking method and reduce the charging per hole from 6 kg to 3 kg per hole and keep the same advance rate for this tunnel. The results are presented in the third part of this paper. In the second part we present the results of the decking mode in shaft. The use of the electronic initiation system in tunnel construction provides the users an effective tool to improve the overbreak/underbreak and keep the vibration at a low level with a large gain on the overall project schedule and budget. This what we want to demonstrate in this paper.

Jan 21, 2025