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By Alan Diaz Butron, Eng. Thierry Bernard

"In tunnel blasting the most challenging objective is definitively obtaining the maximum advanceassociated to a minimum overbreak. Achieving 100% of advance with no overbreak is the targetchallenge by Chavimochic Consortium. Chavimochic Special Project is an irrigation system that extends throughout much of the coast of the La Libertad Region, on the north coast of Peru. In 2012, it began management for construction of the third and last stage of CHAVIMOCHIC to irrigate lands of Chicama Valley, North of Trujillo. This project of 13 Km (8 mi) of various tunnels, it's a combination of technology and daily optimization by experienced people, which allow to accomplish the objective. Achieving this advance with no overbreak provide a huge saving on time. This paper describes the method, technology used, and the results obtained on more than 600 blasts done with conventional initiation system on the first 3 km (1.86 mi)."

Jan 1, 2017

By A. Ravi Kumar

A trench is a structure to accommodate fluid carrying pipelines for water, gas, petroleum products etc. Trench serves the purpose to haul the fluids in bulk over long distances safely and economically. Use of pipeline for moving oil and gas was essentially a post World War II development, but now it has acquired its own importance.

Jan 1, 2008

By M V. Van Bers, A L. McAnuff, A Curic

During the Summer of 1997, rock excavation was carried out for construction of the Centre Block Underground Services building (CBUS) abutting the most historically significant structural complex in Canada, the Parliament Buildings in Ottawa. Controlled blasting was required for the removal of 25,000 cubic metres of limestone bedrock within the ten week time window of Parliamentary recess. A test blast program carried out in 1996 had established that close blasting was viable even within the very restrictive limits considered necessary to preserve the structural and cosmetic integrity of these historic structures. In total 300 blasting operations were required to complete the excavation, including the 20 test blasts conducted in 1996. Based on attenuation characteristics established for the site during the trial blast phase, the blasting contractor proposed excavating the CBUS site in three zones. Each zone contained differing drill patterns, depths and explosive loads. Vibration intensities, air concussion levels and displacements across representative existing cracks were measured and recorded at numerous observation points within and around the Centre Block and the Library of Parliament, as well as on the grounds of the Parliamentary Precinct. The blasting portion of the excavation was completed within budget in less than eight weeks, well within the tune window available. Comparison of very extensive pre and post-blast condition surveys revealed no damage to the existing structures on Parliament Hill as a result of these operations.

Jan 1, 1999

By M. Ganster

Austria’s biggest supplier of oil and gas, transports gas through the West Austria Gasline for domestic consumption. In addition, the OMV also works as gas carrier and ensures the transit into neighbouring countries.

Jan 1, 2010

By Claudio Lechuga, Carlos Scherpenisse, Juan Rafael Otaiza

From the analysis of drilling process, Block Model information, drilling pattern data and expected fragmentation targets; GBlast® software optimizes the explosive charge design in order to standardize the particle size of each blast.

Feb 1, 2020

Currently there exist several explosive quantity-distance (Q-D) rules variously exercised by most countries to protect personnel and property against the effects of accidental explosions. These regulations apply to manufacture, transport and storage of explosive products. This paper reviews the technical basis behind these regulations, as they apply to commercial and military explosives. The characteristics of a blast wave and missiles issuing out of an explosion site and their role in determining the level of damage to a target are discussed. The need for further research on the effect of detonation of charges of non-standard geometry, and under confined conditions such as tunnels is discussed. The challenge in estimating the net quantity of explosives involved and calculation of its TNT-equivalency is also highlighted.

Jan 1, 2011

Investigating blast vibrations typically utilises scaling and attenuation models for prediction of vibration amplitude over a range of charge weights and distances. A number of generalised relationships have been established from many years of far-field data analysis, where small changes in charge weight and ray-path distance are less critical. Under far-field conditions, small variations in local geology or geometry do not significantly affect the vibration scaling behaviour over an expected range of data. In the near to intermediate-field (less than 5 times the explosive charge length), small variations in wavepath and rock mass conditions between a blast and a monitoring point can greatly affect the outcome of vibration modelling. This case is especially true for underground blasting in sublevel open stoping, where the paths of blast-induced vibrations regularly encounter voids and preconditioned ground.

Jan 1, 2010

By Robert Hopler

GEO. M. MOWBRAY’S REFRIGERATOR CAR FOR THE SAFE CONVEYANCE OF EXPLOSIVES. It is a fact well known to all miners who have used nitro-glycerin, or any of its adulterations, commonly known as dynamite, rendrock, Hercules’ powder, dualin, vigorite, etc., that when congealed, these compounds cannot be exploded, and in this congealed state — say at temperatures below 40° F. — they can be handled with no more danger than a box of soap or a can of lard. If, then, the atmosphere by which this class of explosives is surrounded, during transportation, be maintained below 40° F., explosion is practically annihilated. Therefore, I constructed a refrigerator car, with cells for every box of the explosive; and two years of railroad transportation confirms our ten years’ experience in teaming in wagons, that this class of explosives can be transported in perfect safety, as above described.

Jan 1, 2011

By Gungor Tuncer, Ali Kahriman, Abdulkadir Karadogan

In the bench blasting, the realisation of an economic, and safe blasting is only possible with a reliable blasting design on condition that considering all sequential activities such as drillingblasting, excavation-loading, haulage, crushing (especially primer crushing). Here what we mean with a good, and reliable design is that ensures an almost displaced, adequately swelled muckpile with desired fragmentation degree for the loaders effectivity, and succesive usage. Meanwhile it must also has no environmental problems such as ground vibration, air blast, and rock flyings, or at least these matters have to be minimised. Two main parameters which have generally being questioned to achieve a safe and economic design on any rock conditions, are specific charge, and burden. In the condition of determining these elements, the other blasting parameters could be calculated according to them, and the blasting design could be completed. Within the scope of this study, it was aimed to determine the optimal blasting conditions of gypsum which is major rock unit of overburden at Sivas Celestine open pit mine. First of all, the engineering (mass, and material) and digging difficulty classifications of gypsum were done according to the current classification systems by using the results of field and laboratory studies. Then the blasting system which was being used on all rock units, was considered, and the necessary data were obtained. After previewing the site properties, predesigns were done, and applied by adopting Langefors design model. The necessary adjustments were done before, during, and after the shots, and the applications were observed. In order to determine, and record the data from each shots properly, a practical form was developed, and all data were transfered to these forms which give information about the blasting results such as muckpile displacement, and height, average particle size, back break, and rock fly existence, number of boulders etc. The blasting parameters such as burden, hole diameter, hole inclination, the amount and position of primers, bench height, delay sequence, and blasting geometry were considered for the iteration of each shots. During the applications, ANFO, gelatine dynamite, and electric delay detonators were used as explosives.

Jan 1, 2004

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 Ethan Steward, Kyle Perry

Underground coal mines have several dangers, one the most hazardous of which is the possibility of an explosion caused by the ignition of methane gas. To reduce ventilation costs, coal mines have the option to close off abandoned areas that are no longer active with structural seals to keep an explosion from propagating into working areas of the mine. These seals must be designed to withstand different pressure levels based on the potential of the atmosphere behind the seal to become explosive, either 50 psi (345 kPa) for inert atmospheres, 120 psi (827 kPa) for non-inert, and over 120 psi (827 kPa) for special cases. Though seals have been designed to resist the overpressure, none have been evaluated for their resistance to the impact of heavy objects. Underground explosions produce high velocity gasses that, traveling through mine openings, may propel objects in the mine at a high velocity causing them to impact and damage the mine seals. Seals damaged in this manner may no longer hold the pressure they were originally rated for and may fail during subsequent explosions or leak explosive gasses into active workings. To test the effects of impact on mine seals, a projectile generator and two seals have been constructed. The projectile generator is a 12-inch (30.5 cm) inner diameter steel pipe with a 4-inch (10 cm) wall, is 8.5 feet (2.6 m) in length, and sealed on one end. Projectiles are propelled by a charge of black powder with a wooden wad and are held in place by foam sabots in the bore. This system, combined with the large bore, allows firing of many different potential projectiles that may be found in an underground mine at a high velocity into the seals. The velocity of each projectile is measured by an infrared chronometer which can later be used to determine its impact energy. Impact effects on the seals are measured using strain gauges, LIDAR scans before and after impact, high speed cameras, and visual inspection. The focus of this paper is on the projectile generator design and initial testing.

By Paul Worsey, Matthew Coy

In the blasting industry, many different techniques are used to estimate and examine the effects of varying explosives and blast designs on the breakage of a rock mass. The overall objective is to find a cost-minimized blasting solution that also conforms to the legal and environmental concerns related to blasting. A major drawback to current blasting methods is the inability to account for "caprock," or a thick overlying layer found in sedimentary rocks that creates large amounts of oversize blasted material, especially on the top of a muck pile. This can lead to underestimating oversize in shots with massive top layers. A better fundamental understanding of blasting processes with caprock is required.

Jan 1, 2018

By D. Scott Scovira, Remi Proulx

The Meikle Mine is a high grade, underground gold mine utilizing primary-secondary longhole open stoping with delayed backfill to produce 3000 stpd of ore. Hot and reactive ground conditions were encountered early on in the mine life. Ground temperatures up to 330” F were measured. In the early stages of mining, the mine experienced premature detonations using different explosives. The learning curve to safely mine this high-grade gold deposit in hot and severely reactive ground was indeed very steep. Currently, the Meikle Mine uses a special buffered bulk emulsion in all blasts to address hot and reactive ground concerns. In addition, exacting procedures are also followed to ensure safe work with explosives. The combination of new explosives technology and strict loading procedures permits high mine productivity with the highest degree of safety.

Jan 1, 2000

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 Sandy Tavelli, Thomas L. Barkley

This discussion will present a case study in developing solutions to a metropolitan quarry’s public relations, legal, environmental, and productivity problems. It details an extensive and detailed project to address the blasting practice in a medium sized quarry that is surrounded by residential and industrial zones. The principle work was done over a four-month duration during the normal production season. It included detailed drilling and blasting audits for baseline information. In addition, geologic characterization, seismic modeling, correction of deviations from best practices, and implementation and monitoring of precise electronic timing to provide dramatic solutions for the quarry. The quarry is in the near suburbs of a large metropolitan city. It is framed on two sides by residential municipalities and on two sides by industrial zones. At the start of the project, the quarry was in court as a result of the lawsuit by one of the neighboring towns that was suing to close the quarry. The lawsuit had progressed to the advanced stage where in the Judge had appointed an arbitrator to make the decision of continued operation. This arbitrator was to observe our progress and recommend to the Judge the disposition of the case.

Jan 1, 2004

By E. Lentilucci, A. Dey, X. Liu, A. Datta, S. Ghosh

The segmentation of quarry blast smoke plumes is a crucial research area that has the potential to enhance safety, environmental monitoring, object detection, and regulatory compliance in the mining industry. Smoke plume segmentation can be used to identify the spatial extent and temporal evolution of smoke plumes generated by the blast. This information can be used to improve the understanding of blast dynamics and optimize blast designs. Furthermore, smoke plume segmentation can assist in identifying potential environmental and health hazards associated with the release of smoke and dust particles into the atmosphere during quarry blasts. However, many current smoke plume segmentation algorithms are designed for segmentation of smoke plumes from fires and are not suitable for segmentation of plumes from quarry blasts. The proposed method in this paper leverages the video frame captured before the blast as a stationary background image, which helps to reduce other confuser objects present in the image along with a selfadaptive clustering method. The color channels of the image are utilized based on the different contrast properties of the smoke, with a self-adaptive gradient compensation applied for edge detection of the smoke plume. This approach offers a novel and effective way to segment smoke in quarry blast analysis, with potential applications in the calculation of noxious gas volume and concentration within the plume. Compared to other algorithms, our method improves accuracy, decreases the false alarm rates, and reduces the overall miss rate. Overall, this paper contributes to the research on smoke plume image segmentation, particularly for quarry blast smoke plumes, which possess unique characteristics that require specialized algorithms for accurate segmentation.

Jan 1, 2024

By Tom Watts

Bulk Security Best Practices

Jan 1, 2006

By Brandon Fryman, Josh Hoffman, Rhys Baker

A post-detonation debris collection project was led in conjunction with a large ammonium nitrate (AN) railcar detonation conducted by the Department of Homeland Security-Transportation Security Administration, Department of Defense-Combating Terrorism Technical Support Office, Sandia National Laboratories, and the U.S. Army Dugway Proving Grounds. This important work will aid in underpinning algorithms used in a Quantitative Risk Assessment (QRA) tool.

Feb 1, 2020

By Dr. Calvin J. Konya, Anthony Konya

Blast violence has always been a criteria that has been analyzed without a quantitative approach relying on opinions of those viewing the blast and oftentimes does not transfer between open-pit mines, quarries, and construction projects. Added to this confusion is that on many regulate projects, such as U.S. Army Corp of Engineers construction projects, the definition of "flyrock" or violence can vary, and contractors must be able to meet this requirement. This project analyzed hundreds of blasts from various construction projects to develop a new metric to determine blast violence - the Violence Factor.

Feb 1, 2020

By Dr. Calvin J. Konya, Anthony Konya

Blast violence has always been a criteria that has been analyzed without a quantitative approach relying on opinions of those viewing the blast and oftentimes does not transfer between open-pit mines, quarries, and construction projects. Added to this confusion is that on many regulate projects, such as U.S. Army Corp of Engineers construction projects, the definition of "flyrock" or violence can vary, and contractors must be able to meet this requirement. This project analyzed hundreds of blasts from various construction projects to develop a new metric to determine blast violence - the Violence Factor. If a blast is fired using 1.25" (32 mm) diameter product and a 10-foot (3 m) bench, vertical uplift of 60 feet (18.3 m) would be considered extreme and violent by any professional in the industry. However, a 100-foot-high (30.5 m) bench using 12" (305 mm) bulk product, having a vertical displacement of 60 feet(18.3 m)might be considered typical or non-worrisome. This is where violence factor is beneficial as itprovides a system of scaling the violence of a blast based on the bench height to give manager a keyperformance indicator (KPI) which is easy to monitor and can provide a large amount of information onsite-specific design variables for their performance on blasting and the end-results of the blast. The Violence Factor of a blast is an integer which is scaled to determine how high vertical uplift of a blast is compared to the bench height. This project analyzed numerous blasts to determine what blast design variables contribute to violence. This violence has also been shown to occur when a non-optimal breakage mechanism, cratering, occurs and the design criteria that lead to this cratering. Finally, this paper will present typical results of various levels of violence including backbreak, fragmentation, and muckpile configuration.