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By Chanhwi Shin, Hyeongmin Kang

Mine optimization is a key strategy in the mining industry that focuses on improving the efficiency, productivity, and sustainability of mining operations. To achieve mine optimization, digitalization is essential for modernizing mining operations and attaining optimal performance. Due to the importance of mine digitalization, various software and platforms have been released to support this effort. Furthermore, by integrating these advanced technologies, mines can enhance processes, leading to significant economic and operational benefits. However, integrating data from various sources and collaborating across different platforms remains a significant challenge in the mining industry. Generally, data for mine optimization, such as mapping, smart drilling, FMS (Fleet Management Systems), fragmentation analysis, or vibration analysis, are collected and analyzed separately on different platforms. This separation makes it difficult to aggregate and utilize data comprehensively for overall mining process optimization. During the digitalization process, obstacles arise due to these complexity, variability, and sharing issues of data across different maker, sources, and methods. These challenges highlight the need for seamless integration to achieve optimal mining operations. Thus, this study applied a total solution that can cover the entire Drilling and Blasting (D&B) processes. The blast design was performed using actual terrain mapping data, and drilling and charging were conducted following a guide based on the blast design plan. After blasting, loading and hauling distances and fuel consumption were measured, and fragmentation for each blast was evaluated. All measurement tasks were automated to minimize human error. By collecting all data in one server, it became possible to perform an overall evaluation for each blast, allowing the identification of optimal values. In conclusion, to evaluate the optimization effects for each mining process, one month of integrated data collected on a single server was used. Compared to the period before the Total solution was implemented, there were notable improvements: a 25% enhancement in hole spacing, a 60% improvement in floor flatness, a 23% reduction in average fragment size, and a 19% improvement in fragment uniformity. Regarding cost savings per blasting volume, the improvements were 11.7% in drilling, 9.3% in explosives, 7.6% in loading, and 17.5% in hauling.

Jan 21, 2025

By Galetakis M., Deligiorgis B., Xiroudakis G.

Fragmentation prediction is important in surface mining to optimize downstream processes such as loading, hauling, comminution, and beneficiation processes. Traditional approaches, such as the Kuz-Ram model, image-based fragmentation analysis, and numerical simulations, rely heavily on large datasets acquired after blasting. Moreover, due to the inherent limitations in each method there is an underestimation of fine and coarse fragment sizes, when applying these models without prior knowledge regarding the fragmentation distribution. These drawbacks are restricting their use only in post-blast parameter prediction. In response to these inefficiencies, this study presents a deterministic fragmentation prediction methodology based on a single-blasthole model. The model simulates the formation of the damage zones around a blast hole based on the number of cracks within a distance from the centre of the blast-hole and correlates them with an estimated fragment size in each domain. A fragmentation distribution from the literature is employed to validate the proposed approach and the results are compared with those generated using a modified Kuznetsov model. This approach aims to enhance blast design decisions by enabling pre-blast fragmentation prediction. Based on this, blast designs could be estimated depending on the desired fragmentation before blasting, giving the opportunity for a tailored to local rock properties optimization.

Jan 26, 2026

By Jianping Li, Ernesto Villaescusa, Kelly Fleetwood

During blasting, stress waves propagate through a rock mass, inducing stress and strain changes. This applied deformation affects intact rock, existing discontinuities, mine excavations, and engineered structures in the proximity of the blast. Traditionally in blasting, stress waves are quantified in terms of peak particle velocity (PPV) or peak particle acceleration (PPA), based on the method of measurement and the specified allowable tolerances. During analysis, the peak particle motion is coupled with an explosive source through various scaling laws to develop rock-specific attenuation relationships. Some studies have expanded this practice to the development of damage threshold values based on measured or predicted peak particle velocities. PPV-related thresholds are generally based on empirical models, where observation of overbreak, cracking, or fall-off are used to quantify damage. This method is often paired with the application of elastic plane wave equations to calculate the blast induced strain or the PPV threshold for tensile rock failure. Other factors that must be viewed critically in such models are the methods used to collect and analyse blast vibration data and the application of inappropriate vibration attenuation relationships.

Jan 1, 2009

By Elliott Giles

"Measuring a blast’s performance based on the bucket fill time or “diggability” has always been achallenge due to the subjectivity generally involved. The diggability of a blast is often based onopinions and speculation without the data to properly support the claim. This paper focuses howthe blast design can impact diggability and how it can be properly measured."

Jan 1, 2016

By P. N. Worsey, M. Schmidt

Many advanced military systems and civilian power generation concepts postulate the availability of compact sources of electrical power capable of delivering gigawatts over microsecond time scales. For example, such a compact power source is essential for future practical pulsed high-powered microwave sources. An explosive-driven flux-compression power generator (EDPG) could fill this requirement. A basic strength of this concept capitalizes on the inherent high energy density storage capacity of modern chemical explosives. It relies on the physics of magnetic flux compression to convert that stored chemical energy into very large amounts of electrical power over short time scales. The generator also has the additional advantage of employing the same types of explosives that are already routinely used in conventional munitions. However, the self-destructive nature of this type of power generator places serious limitations on power pulse-lengths and ranges of applications. This paper describes how a multi-disciplinary team led by researchers from the University of Missouri-Rolla (UMR), Texas Tech University (TTU), and Texas A&M University was awarded a grant by the U.S. Air Force Office of Scientific Research to perform basic research to resolve several fundamental EDPG problem areas. Described are the utilization of UMR’s extensive explosives research expertise and facilities to investigate questions of energy conversion efficiency and the mechanics of energy production. Also, UMR explosives researchers will provide inputs to improved dynamic computer models of the complex, intertwined physics and chemistry operative in these devices. In addition to explosives expertise, UMR provides facilities for basic explosives material research, as well as the storage, machining, and formulation of explosives. UMR researchers are also using test facilities and data collection equipment at the Rock Mechanics and Explosives Research Center and at the UMR Experimental Mine to perform “proof of principle” and subscale tests of explosive-driven flux-compression power generator components. An integral part of the paper is a description of the development of an extreme intensity flash system by UMR and TTU to allow for the high-speed photography of EDPGs in operation. This multi disciplinary research program offers major advances regarding the size, weight, and electrical characteristics of compact EPDGs. Such breakthroughs could dramatically accelerate the practical realization of systems currently under study. Also, these power sources may have far reaching relevance to other Department of Defense and certain commercial compact power applications.

Jan 1, 2000

By Felipe França Sitonio

Parameter’s control of explosives used in blasting operations have become more relevant over the years, bringing a better understanding of detonation performance. Giving into consideration that bulk emulsion density’s variation reflects directly on blasting results due to its importance in product sensitivity and velocity of detonation (VOD), blast designs are conducted assuming that cup density measurements are reliable and explosives gassing agents will perform as per specifications. Nevertheless, confinement conditions in boreholes like temperature, presence of water and surrounding circumstances of rock mass are often neglected on predictive modelling and off-site measurements. This paper describes the assembly of a device equipped with pressure sensors and its utilization in confined boreholes of an open pit mining operation, aiming to obtain in situ monitoring of density variation in several explosive columns. After we developed a software to get and process data of a hardware prototype and the device functionality was validated in water, oil and quarry mining experimental trials, 7 of 291 boreholes in a gold mine operation were chosen to be monitored with two probes each, placed at the top and at the bottom of the explosive column profile. The results obtained enabled a comparison between the bulk emulsion density variation when acting in different environments, since we selected boreholes with diameter of 101.6 mm (4 in) and 139.7 mm (5.5 in) and some with presence of water. Besides the increase of explosive density with depth related to hydrostatic pressure increase, we found an overall error of 6% in cup density measurements when compared with sensors placed at the bottom of boreholes and 2% when compared with sensors placed at the top of explosive column. These findings provide detailed insights into how bulk emulsion explosives behave in different circumstances including depth and borehole diameter, giving the opportunity to re-evaluate blast design parameters such as its geometry, sequence pattern, charging profile and explosive composition.

Feb 2, 2020

By Barbara Rutter, Phillip Mulligan

This research investigates how changes in shock tunnel geometry affect the pressure versus time waveform. The Large Arena Test Simulator (LATS), which is composed of four different rectangular sections connected by three expansion sections, was used to determine how the changes in geometry affect the shock wave profile.

Feb 1, 2020

By N. Skopak, C. Aimone-Martin, J. Redyke, B. O. Meins

PipeBlast is a spreadsheet-based calculator based on research conducted by Southwest Research Institute (SwRI), used by the pipeline industry to determine if proposed blasting planned near existing pipelines can be safely executed. The two factors determining “safe” are blast-induced pipe wall hoop stresses and predicted peak particle velocity (PPV) at the pipeline. Although methodology used to predict hoop stresses is somewhat sound, predicted PPV amplitudes are highly exaggerated based on inappropriate attenuation models developed using spherical explosive charges of limited charge weights, placed in soil adjacent to model pipelines that do not represent rock blasting. Hence, pipeline companies readily reject well-design blasts and limit scaled distances far beyond what is reasonable and cost-effective to pipeline owners. Full-scale trench blasting in rock was conducted near a 24in (711mm) diameter operating API 5L X70 grade steel pipeline in Texas to compare PipeBlast model predictions with a Ground Strain Model (GSM) based on field measurements of ground motions on the surface and at the pipeline springline. Results of the GSM were compared with pipeline strains measured using wire gauges mounted on the Springline. The comparative results showed that a site-specific velocity propagation model provided good estimates of ground strains that are replicated on the pipeline walls in terms of hoop and longitudinal strains. Trench blasting 28ft (8.5m) from the pipeline produced ground motions of 7.6in/s (193mm/s). At this ground motion amplitude, the factor of safety defined as the allowable stress divided by the combined operating and blasting hoop stresses was reduce from 3.04 in the absence of blasting to 2.98. This paper explains the research and findings on which PipeBlast is based and presents an alternative approach to predicting blast-induced pipe wall stresses based on site-specific velocity propagation measurements and a ground strain model.

Jan 1, 2024

By Catherine Johnson, Barbara Rutter, Phillip Mulligan

Shock tubes, shock tunnels, and blast tubes have been widely used by explosive researchers and shock wave investigators to understand the characteristics of shock waves. Rectangular, cylindrical, and conical are the three simple geometries commonly used in shock tube and shock tunnel testing. These geometries result in shock waves that resemble the Friedlander curve’s simple exponential decay. However, geometries that are more complex have not been studied. This research investigates how changes in shock tunnel geometry affect the pressure versus time waveform. The Large Arena Test Simulator (LATS), which is composed of four different rectangular sections connected by three expansion sections, was used to determine how the changes in geometry affect the shock wave profile. Shock wave profiles were measured inside and outside the LATS to investigate the geometry’s effect. A representative shock wave profile from each geometry and open-air explosive testing were compared visually showing the geometries effect on the shock wave profile. The LATS produced a waveform with four pressure peaks behind the initial shock front, which were found to be associated with the four rectangular sections. The resulting pressure trace was compared to pressure traces from simulated urban bombings. The number of turns in an urban environment equated to a new peak, which is caused by additional expansion sections of the shock tunnel. From this observation, complex geometry shock tunnels can be purpose built to simulate an explosion in an urban setting. The use of shock tunnels with complex geometry in simulating urban bombings can allow for numerous representations and a better understanding of profiles produced during an urban bombing or similar scenario.

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 A. Ribeiro

The effective utilization of resources and process optimization play a crucial role in the sustaining and growth of overall businesses. This principle holds true in the mining sector, where particular attention is required during the comminution steps. This necessity arises from the fact that mining operations often consume substantial amounts of energy in mineral processing. Therefore, it becomes imperative to thoroughly study the integration of comminution steps. In many instances, an approach to be studied is the operation commencing with the drill and blast phase and culminating in the grinding product process. Nevertheless, establishing an optimal integration between drill and blast operations and the grinding phase is a complex undertaking due to the direct influence of rock characteristics on this process. And in many cases, the complexity and variability of such physical characteristics makes mining operations to ignore such influence. Consequently, Enaex Mining Technical Solutions (EMTS), in collaboration with Lundin Mining's Chapada Mine engineering team, and with the assistance of Hatch Consulting and Technology, has undertaken a comprehensive study aimed at enhancing mill throughput at the Chapada operation. The basis of this study lies in characterizing the rock masses present in the Chapada Mine to gain a deep understanding of the material that needs to be comminuted. Subsequently, the mineral processing team determined the most suitable size distribution for the Run-of-Mine (ROM) material. With this information, the drilling and blasting team built a site-specific blast fragmentation model, able to simulate various blast design scenarios. This approach enabled to optimize the utilization of available drilling and blasting resources while striving to achieve the optimum ROM characteristics. Since 2021, the Mine to Mill methodology has been progressively implemented at the Chapada Mine. As a result, the blasting engineering team now utilizes the blast plans generated by the fragmentation model simulations as a foundation for designing blast plans that align with the operational and financial capacities of the mine. Overall, it was predicted that this implementation could lead to an average increase in mill throughput of 13-22 % depending on blend feed, once all recommendations are implemented. Even with partial implementation, plant results demonstrate a 5 % increase compared to the period before the Mineto-Mill project, without any coarsening of the associated grinding product size.

Jan 1, 2024

Prepare ATF Report of Theft or Loss (ATF Form 5400.5). A Report of Theft or Loss - Explosives Materials must be prepared when it is discovered that explosive materials are missing from inventory. Submit the original to the U.S. Bomb Data Center and keep a copy for your records. The form can be obtained from the ATF Distribution Center or from www.atf.gov. Although the U.S. Bomb Data Center should be notified as soon as possible, Federal law requires notification within 24 hours of the discovery. A full inventory check is also highly recommended (but not required) to locate missing explosives and to prevent future losses.

Jan 1, 2008

By Cary Moffat, John Kita, Rick Walker

The Lac des Iles Mine, in an isolated area of NorthwesternOntario is a relatively new open pit platinum and palladium mine. They were encountering problems with the equipment and production scheduling when ramping down to begin production on the subsequent benches. A co-operative effort between Lac des Iles Mine operation people, ICI Explosives, and the mines drilling and blasting contractor - Consbec Inc., resulted in a decision being made to use full depth sinking cuts to provide access to the next bench.

Jan 1, 1996

By Kenneth Eltschlager

Blasting represents the highest risk of any surface coal mining activity that could result in injury and/or property damage off the permit area. In addition, blasting related issues e.g. flyrock, vibrations, air blast, etc., are responsible for a large percentage of citizen complaints. Thorough and consistent regulation of individuals certified to conduct blasting by the Office of Surface Mining Reclamation and Enforcement in Federal Program states and on Indian Lands under Federal jurisdiction is vital, as it serves to: facilitate coal production to meet the nation’s energy needs; protect people and property on and adjacent to Federal mining permits; form a basis for states to grant reciprocity certificates to Federal blasters; and be a positive example to primacy states. OSM issues Federal blaster certificates for blasting on Federal surface coal mine permits. The certification program includes experience, training and testing components similar to many of the states. But where a state program may focus on the specific blasting applications within its boundary, the OSM certificate requires a very diverse test to cover all potential blasting applications and products across the nation. Therefore, the Federal certificate is a good surface mining credential for blasters anywhere in the United States.

Jan 1, 2010

By Mark Spaniel

Computer 3D modeling to evaluate the potential underground blasting fragmentation performance based on rock within calculated damage radii along drillholes, as well as the burden distance from explosives along each drillhole. The results estimated from the 3D computer models closely predicted results found in the real world testing.

Feb 1, 2020

By Walt Meglasson

The Kaiser Aluminum Company Smelter, one of several in the Pacific Northwest, was built in 1942 and operated by the Olin Company during World War II and then purchased by Kaiser Aluminum after the war. At its height, the facility employed over 350 workers and was capable of producing 73,000 tons of aluminum per year. It was closed in 2000 through a combination of rising electrical and labor costs, and the inability to compete with more up-to-date foreign facilities.

Jan 1, 2008

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 Travis A. Davidson, Ralph E. Burnham, Cathy Aimone-Martin, J. Kelly Ratliff

Blasters face a long list of tasks to execute daily—from vehicle inspections to blast design and layout, hole loading and tie-in, securing the site, and finally, safely executing the blast. Good practices and, in most cases, regulations and requirements necessitate documenting their work, specifically their blast report. While some blasters use paper forms, others use electronic means to streamline the process. The authors have served as attorneys and expert witnesses in representing companies and individual blasters in numerous administrative and legal matters in which documentation of the blaster’s work was both critical and detrimental to the effectiveness of defending their work. This paper discusses in a case-study manner the authors' observations concerning good blast report format, specific observations around electronic and paper report completion, record-keeping, seismograph setup and recordkeeping, video and photo documentation, internal auditing, and other topics related to documenting the blast. The paper aims to serve as a discussion guide for blasters to improve their blast record-keeping process, develop better practices that effectively document their work, and allow them to defend their work should a claim arise concerning their operations.

Jan 21, 2025

By Steve Linehan, John Toedter, Kelly Williams, Mark Herman, Laura Connor, Catherine E. Johnson

Minimum safe distance (MSD) calculations are used widely in military applications to determine safe standoff distances for breaching personnel. Accurate safe distances and an understanding of blast wave propagation are critical to preventing traumatic brain injury. These calculations are often based on spherical charges in open air. However, applications including explosive breaching use planar charges rather than spherical. Previous studies analyzed the shock propagation of a square planar charge of sheet explosive and concluded the anisotropic pattern conflicted with the Kingery Bulmash (KB) and MSD spherical models. It has been determined that these predictions do not adequately predict the realistic pressures in all directions and the trend has shown to be consistent across multiple charge geometries. In this series of experiments, pressures were collected from reference spheres and rectangular geometries of detonating cord and sheet explosive commonly used in breaching and improvised demolition for this comparison. This common configuration showed pressure differences at varying angles to the charge with the highest pressures measured at the 90° position perpendicular to the “door” to be breached. Lower pressures were found at the 0° and 15° positions where the breachers would normally be standing. The reflected shock from a surface such as a door was incorporated in a semi-confined situation and added to the shock observed by the breachers. Urban environments include many surrounding structures for these reflections to occur and further testing is necessary in such an environment to determine the full-scale impact. These findings may be useful to develop improved MSD calculations for breaching applications based on charge geometry, orientation to the blast, and nearby structures.

Feb 6, 2023

By Samir Garcia, Alain Mestanza

This technical work was carried out in an open pit copper mining unit, located in central Peru, which has a daily production of 440 thousand tons per day. Currently the pit consists of three mining phases, however, in phase 05 north, there is the construction of a shaft with a height of 375 meters, the function of this structure is to collect and drain the water coming from the pit, there is the importance of preserving its stability and keeping it operational, guaranteeing the sustainability of the operation. For this, a controlled blasting plan was developed that goes from level 4530 to level 4455 to place the central well on a bench, reactivating the pools.

Jan 21, 2025