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By Felix Degold, Mark Ganster

Achieving a customer optimized fragmentation by using robust data from new technologies e.g. GPS positions of boreholes, fragmentation analysis to calibrate the geology and fragmentation prediction models. The inclusion of the collected data into the blast’s design makes it possible to accomplish a desired particle size distribution.

Feb 1, 2020

By Z X. Zhang

If the iron ore loss is 15% in the process of mining, the total iron ore loss in the world will be about 461 million tons, this is equal to the total production of 230 iron ore mines each of which produces 2 million-tons of iron ore per year. Based on a series of blast tests in the Malmberget mine, this paper shows that ore recovery can be markedly increased by improving blasting technology such as choosing a correct primer position and making use of shock wave collision. The paper further suggests that a high ore recovery can not only reduce natural resource loss and mining cost but also prolong the life of a mine. In addition, the paper shows an example of reducing blast-caused rock damage in the roofs and walls of underground drifts (tunnels) by using new blasting methods in the Malmberget mine. Finally, the paper shows how the Malmberget mine has successfully reduced the ground vibrations, without adversely affecting fragmentation and ore recovery in sublevel caving mining.

Jan 1, 2014

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 Gordon C. Petersen, Gary A. Almeraris

This paper describes the controlled blasting techniques required to mine a rock tunnel section of a main interceptor located in the Boston Metropolitan area. The 3m (10 ft) x 2.8m (9.25 ft) horseshoe shaped tunnel was driven 490m (1600 ft) by conventional drill and blast methods. The geology varied round by round and consisted of five highly faulted and jointed igneous rock types. The tunnel intersected numerous slickenslides and open mud seams which hampered both drilling and loading operations. Smooth blasting wee critical in order to keep overbreak tc a minimum in this extremely hard but blocky ground.

Jan 1, 1991

By Ery Wardhana, Stefanus Jagad, Relinda Sanistya, Hasucita Tausi, Rido Situmorang

The blasting process is one of the most high-risk activities in mining operations. Shotfirers and blasting crews face hazards from slope failure, toxic gas and fumes, or unstable ground condition every day of the blast. But on the other hand, to ensure all of the holes are detonated, shotfirers are required to reenter the location to check. With advances in technology, nowadays the use of drone in mining is not something that is rarely seen. It has been used for mapping and slope-monitoring. This paper will discuss the application of drone for blasting process in a mining pit in East Kalimantan, Indonesia. By using drones, it is not only safety factor which can be improved but also operational efficiency and technical analysis. The duration it takes for post blasting process can be reduced because the drone can directly enter the location after blast. The technical analysis for the blast can also become more comprehensive, as the before-after photos and video documentation can be taken with wider view. It helps with fly rock calculation and fragmentation analysis too.

Feb 6, 2023

By G. Walsh, M. T. Wild

In this paper the performance effects of linear shaped charges will be discussed. Different sized charges were tested and reviewed based on their performance used with a typical detonation method vs. detonation with a line wave generator. The goal of the project was to determine if the linear shaped charge had better performance with an ideally linear wave moving through it, verses a swept wave that is currently used. A line wave generator is a flexible sheet explosive formed into a triangular shape with holes placed in strategic places to cause a detonation wave to become linear across the width of the triangle. A standard linear shape charge with a detonator in the side of the charge was be detonated against a witness plate to get a standard depth of penetration. A second standard linear shape charge with a detonator connected to the top of a line wave generator, the line wave generator placed on top of the linear shape charge, was be detonated against a witness plate to get a comparison depth of penetration. All charges had a standoff 1.5 times the width of the cavity, allowing the data to be compared to the control charge. Computer modeling was intended to be used to predict the results from testing these designs in the field. The actual results were compared among themselves.

Jan 1, 2011

By J. Sanchidrián, A. Fernández, P. Segarra

The combination of chemical analysis techniques as XRF and measurement-while-drilling (MWD) technology in underground mining is a novel approach to gather comprehensive on-line information about physical and mineralogical data. In this work their integration is investigated aiming to delineate the ore/waste boundary. The input data analyzed come from a narrow vein underground mine, where the ore correspond to fluorite, and gathered in two production levels with complex mineralogical characteristics. Two approaches are followed to build a generalizable classification methodology and a site-specific model: a k-means clustering heuristic algorithm to define rock classes based on their physicochemical features, and a machine learning (ML) ensemble model trained with drilling parameters. For an imbalance class problem, a good recognition is obtained for the ore when is related to a high content of silica and for the waste. To predict the ore with low silica content it is necessary to integrate an analysis-while-drilling method to recognize the fluorite content when this mineral is embedded in different rocks. MWD can be employing for the lithologies recognition when representing different structural and mechanical properties between them.

Jan 1, 2024

By Braden Lusk

The problem of predicting damage in densely developed areas due to incidental or malicious explosions is one of considerable importance to local, state, and federal governmental bodies. The difficulty of making such a prediction is confounded by the urban canyon phenomenon as the shock wave intensifies or rarefies depending upon the particular arrangement of buildings. The specific method detailed herein used a Computational Fluid Dynamics solver, ANSYS AUTODYN, to operate on Geographic Information Systems data, ArcGIS, which captured the geospatial relationship between the various buildings in downtown Oklahoma City, prior to the Murrah Building bombing. The model of Oklahoma City was first developed using the building footprints and elevations provided by the ArcGIS database. Due to the sheer size of the problem, the model was then subdivided into annular zones of increasing distance from the center of the blast. Each subsection was then solved using an Euler model in a cascading fashion with the output of the preceding model forming the input of the present model. To further reduce computational time, the size of the Euler nodes was increased at each stage as the section area increased. Due to the loss of precision in capturing peak pressure values when using larger size nodes, it was necessary to perform a transformation on the results using one dimensional wedge calculations with higher precision. The Murrah Building bombing event was an excellent case study due to its available ArcGIS data and the level of documentation of damage to surrounding structures due to the blast. The results from the staged CFD calculation were then used to develop a damage potential contour map. The documented incidents of damage in the area surrounding the Murrah building were then compared to the model generated damage potential contour map. Copyright ©

Jan 1, 2010

By Robert Lee, Pertti Paavola

Automated vibration monitoring and web-based data distribution has proven itself on the largest single construction project ever undertaken in Finland. The excavation for the Kamppi Center Project in the center of Helsinki was completed in November of 2003 and involved the removal of over 200,000 m3 (260,000 yd3) of rock and over 1,700 individual blasts. A system was installed, incorporating 37 discrete monitoring points located throughout an underlying metro station, and other surrounding underground and surface facilities. After every blast, vibration data was automatically transferred from the monitoring network to a server database. Stakeholders were able to access and review vibration reports on a password-protected website within 90 seconds of each blast. This allowed engineers to verify that recorded levels were in compliance with established limits, before proceeding with subsequent blasts. The data was also imported into a semi-automated Scaled Distance tool for analysis using linear regression techniques. This was used to determine, and adjust for trends in blast-induced vibration.Copyright

Jan 1, 2004

By Andreas Bienz

The safety of persons from accidental explosions and fires during manufacture, storage, transport etc. of explosives, pyrotechnics, propellants, firework and ammunition is most commonly assessed according to prescriptive rule-based approach: Safety is given when all requirements which are listed in numerous regulations and directives (such as e.g. safety distances, limited quantities, protective installations etc.) are complied with. Such a deterministic prescriptive rule-based approach is quite easy to apply but has got disadvantages, however: The actual state of safety in a specific case is not explicitly and quantitatively expressed, and it is not distinguished between the endangered individuals and the whole group. As a result, the effects of the safety measures cannot be measured. This is why uneconomical and in the worst case useless safety precautions cannot be avoided. In addition, waivers are difficult to negotiate, meaningful and sound arguments for pro and con being lacking.

Jan 1, 2007

By Josh Calnan, Paul M. Holmgren, Abigail N. Styer

Detonating cord is a staple of the explosives industry, used widely in the civil and defense industries. Detonating cord is a thin, flexible plastic tube filled with pentaerythritol tetranitrate (PETN). It has many applications in mining, construction and military disciplines. For civil applications, it is used to connect and initiate a series of blastholes in a desired pattern. In the defense sector, it can be used as a detonating agent, a priming agent or alone as an explosive charge. Research has been done to understand the initiation and detonation physics on the detonating cord. However, its sympathetic detonation characteristics needed to be further analyzed.

Feb 1, 2020

This case history refers to the detonation of the two largest chemical explosions on the Australian continent. An important element of feasibility studies and construction guidance included prediction of fragmentation results and ground vibration effects for the detonation of two very large "coyote" blasts, consisting of mined tunnels filled with explosives. The larger of the two blasts contained nearly 1 1/4 million pounds of explosives detonated instantaneously. The explosives were placed in specially designed tunnels under a quartzite mountain for the purpose of generating rock fill for the main dam on the project.

Jan 1, 1995

By G. Cavanough, A. Torrance

Emulsions have been developed for over forty years to become the most common water-resistant explosives used in the mining industry. An emulsion is a common commodity, with many examples in our day to day lives of one immiscible liquid dispersed in another. They have varying degrees of stability from a few seconds to years. What makes their application in explosives unique is twofold. They contain a high concentration of salts in the dispersed phase and also have a far larger volume of dispersed phase than continuous phase. The continuous phase contains at least 75% by weight of an oxidizer such as ammonium nitrate dissolved in water. The crystallization point of these solutions is often >60oC which means that the formation of the emulsion has to occur at an elevated temperature. Once the emulsion is cooled, its structure helps to prevent the formation of crystals in an otherwise unstable system. At room temperature there is a considerable potential for the small oxidizer droplets to crystallize which is countered by the strength of the oil layer and also the size of the emulsion droplet. If the emulsion droplet is too large then crystals can form which may lead to rapid deterioration of the emulsion and overall crystallization, accompanied by a temperature rise as the heat of crystallization is released from the emulsion. The size of the emulsion droplet is critical in preventing crystal growth and subsequent droplet coalescence and emulsion break down. One method of examining emulsions and understanding their structure is to use optical microscopy to measure droplet size and also emulsion deterioration from shearing, temperature cycling and when contaminants are introduced, such as detergents, different oil types, coating agents and dust particles. This paper reports on advanced techniques to quickly assess emulsion quality and stability

Jan 1, 2024

By Gabriel Gonzalez, Paulo Couceiro, Luis Manriquez, Alejandro Gutierrez, Juan Navarro

A high-stakes blasting campaign was successfully executed at a major open pit copper mine in northern Chile. This operation posed a significant technical challenge due to its immediate proximity to the tailings dam - a critical infrastructure whose structural integrity depends on strict control of blast-induced seismic vibrations. The geological complexity of the area, characterized by upper andesite interbedded with caliche (carbonate), further complicated the operation. This lithological composition, known for its high tenacity and cohesion, posed additional challenges for achieving effective fragmentation, necessitating a highly customized blast design and loading strategy. The campaign included four production blasts and one secondary blast, all executed under the constraint of not exceeding the Peak Ground Acceleration (PGA) threshold of 0.64g, as defined by the Maximum Credible Earthquake (MCE) scenario. To ensure compliance, geophones were strategically installed at three monitoring points (P1, P2, and P3) on the dam to capture real-time acceleration data. The use of specialized blast patterns, precise stemming control, and electronically sequenced detonations ensured that all recorded accelerations remained well below the critical threshold. A total of 496,163 tonnes of material were safely blasted, with 8,452 meters drilled and powder factors ranging from 419 to 594 g/ton. Therefore, this case study exemplifies operational excellence in controlled blasting, demonstrating the feasibility of safe mining near geotechnically sensitive zones through predictive modeling, rigorous QA/QC, and post-blast analysis.

Jan 26, 2026

By THOMAS BAMFORD, Dale S. Preece, Amir Behbahanian, Mick Lownds

An important aspect of blasting is rock movement and final muck configuration. Computer modeling of this process has been done in 2D for many years, revealing insights into the blasting process and enabling some design optimization. Since blasting is inherently a 3D process, 2D modeling misses the 3D aspects of blasting results and can lead to inaccurate conclusions. Software development environments in many fields are evolving in 3D, enabled by steadily increasing computer speed, memory, and software efficiency. These same environments are also available for modeling of many physical processes, including rock blasting. This paper documents the development of 3D blast movement modeling techniques that utilize 3D computational mechanics and modern computing environments to predict explosive induced movement of hundreds of thousands of distinct cubic elements representing the rock mass. Blast induced ore travel and final location can now be predicted with reasonable accuracy and acceptable run times. The importance of Energy Partitioning was documented and demonstrated by GEM-2D (Geologic Element Motion) at the ISEE conference in 2024. This software is titled GEM-3D and includes this Energy Partitioning capability. This paper documents a GEM-3D example of ore movement during rock blasting and demonstrates ore dilution as well as the final location of different rock types as influenced by the blast.

Jan 26, 2026

By Jennifer Williams, Donald J. Berger

Originally built between 1913 and 1916, the Ashton Dam & Hydroelectric Facility has experienced various seepage and piping incidents since completion. Ashton Dam is located within 15 miles (24 km) of the historical Teton Dam failure site and about 2.3 miles (3.7 km) west of Ashton, Idaho. Numerous repairs conducted over the years ranged from filling sinkholes on the crest of the dam to placement of rockfill on the upstream slope to improve seismic stability. In addition, the existing low level outlet works was grouted full and abandoned in 1991 due to significant vibrations induced on the dam during its operation.

Jan 1, 2014

By Khushaal Popli, Vanessa Roeland, Brian Hall, Carl Diederichs

Highland Valley Copper (HVC) has embraced an integrated Mine to Mill approach to comminution since the late 1990s. Previous blasting optimization was carried out through adjustments to blast pattern geometry (i.e., reduction of burden and spacing). This approach proved very effective and HVC reduced the burden and spacing of high energy ore blast patterns to what was considered the practical limit that still allowed for efficient drilling and bulk truck loading operations. While mining in the bottom of the Valley pit near the end of the previous pushback, HVC encountered high static groundwater conditions which enabled the transmission of elevated inter-blasthole pressures that had the potential to exceed safe operating limits for initiation products. This risk was mitigated through an expansion of burden and spacing for the high energy ore patterns, reducing the application of blasting energy and increasing the average particle size in Mill feed.

Feb 6, 2023

By Jeffrey Meissner, Mike Waldron, Charles Dowding

Most studies of crack response have focused on opening and closing of a crack in the plane of the wall in which the crack occurs. Crack movement also occurs perpendicular or normal to the plane of the wall. This paper will examine and compare the in-plane and out-of-plane (normal) response of cracks in two different residences near limestone quarries. In two locations, sensors that measure in-plane and normal displacement were installed side-by-side on the same crack, allowing direct comparison of the two modes of response. In a third location, a perpendicular pair of displacement sensors was installed in a corner of a room to observe the bidirectional response of the structure at a corner. Both long-term and dynamic data were recorded with the same sensors; temperature, humidity, and air over pressures were also recorded to compare blast and weather effects. Measurements show that ratios of out of plane to in plane response to dynamic events can vary. However, the ratios of out of plane (normal) response to vibratory events to that of climatological change is still as small as the ratio for in plane crack responses.

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 Steve Kane

Lightning is a very real problem in the surface mining industry. Today, as adverse market conditions continue to influence the surface coal industry, it has become necessary that all functions of the surface mining process become as efficient as possible. High production with reduced manpower is the winning combination of staying competitive in the market place. We at AMAX Coal are committed to staying in the coal business, but we have always been committed to providing a safe work environment for our people and will continue to do so in the future. Approximately two years ago, our Midwest mines installed state of the art lightning detection and warning systems at our mines. This paper will cover its application at Delta Mine; the benefits and problems encountered, and the impact this system has had on Delta Mine.

Jan 1, 1992