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By Lindsay Wade, Peter Dare-Bryan

Benches in surface mines often contain known areas of ore and known areas of waste, which must be mined selectively. When rock is blasted it not only fragments but is also physically, and non-uniformly, moved. Risks therefore exist of ore being lost if treated as waste and of mill feed being diluted by waste. Both possibilities carry serious fmancial implications.

Jan 1, 2001

By Frederick B. Kuhnow

Harmonic energetic delamination a building is being considered for demolition at a formerly known atomic power lab. The building is within a containment structure under a negative pressure, so that no radioactive material is leaked out to the environment. A new approach was developed to make this work possible.

Feb 1, 2020

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 Francis Otuonye

Rock fragmentation by blasting still remains the most common and cost-effective method of excavating hard rock in mining and tunneling operations. During blasting, the dynamic stresses induced by the detonation of the explosive, in addition to fragmenting the rock in the vicinity of the blast, may fracture the rock at considerable distances from the point of detonation of the explosive. The fractures can result in reduced mine safety, increased costs to support the opening, low productivity and perhaps high ore dilution. Besides the dynamic stresses produced in the rock, air blast overpressure pulses are generated and propagate through the network of underground mine openings. The waves, unable to spread out spherically or hemispherically like blast waves from surface blasting, are forced to propagate by reflection from the roof, ribs and floor down the drift. Blast wave focusing can occur and produce intense shock waves that could damage ventilation barriers such as cement block stoppings.

Jan 1, 1992

By Rafael Tadeu Pinto e Moura, Giorgio De Tomi, Jacopo Seccatore

This paper describes a research and development project in an open-cast mine with the goal to achieve an average P80 of 300 mm (11,8”) in the run-of-mine (ROM) product without altering the existing budget. The project included several variables in the blast design that were not previously taken into account, such as the orientation of natural joint sets in the rock mass, specific energy of the explosive and firing sequence. The new blast design method considered the directions of natural joint sets and determined the drilling pattern and the firing sequence accordingly to favor the movement of the blasted rock along its preferential direction, to reduce its confinement. At the end of the project, it was achieved an average P80 of 304 mm (12”) in the ROM, 50% lower than the one at the beginning of the project. The final blast of the project showed a reduction of 3% of the drill and blast cost, employing the same powder factor and the same drill pattern size used at the beginning of the project. The results achieved show how rock fragmentation is related to variables that are not contemplated in the most common fragmentation models: the firing sequence and the direction of movement in the blast.

Jan 1, 2015

By R Frank' Mammele Chiappetta, Conny Postupack

A major problem that has continued to plague the surface coal industry is blast induced damage to the coal seam. Atlas Powder Company has addressed this situation through seven years of field research in full-scale production environments. Many operations across the United States have been evaluated.

Jan 1, 1988

By Kris Shukla

Noise and vibration produced by blasting generate curiosity and concern from neighbors. Experiments conducted in Sweden, Canada and U.S.A. have established that fine cracks in the plaster--the weakest part of building components--appear at a particle velocity of 4.0" per second or more. Taking into account the margin of safety, the safe zone criteria of 2.0" per second has been established.

Jan 1, 1978

Dear All, I am looking for information about vibrations and effects on fish in pools. A tunnel blast is planned to be carried out as close as 300 meters to a freshwater fish growing plant. What is the vibration criteria for fishes in pools? Your comments will be highly appreciated.

Jan 1, 2012

By J T. Patterson

The mining, quarrying and construction industries are often blamed for causing damage to residential-type structures when explosives are used. The claim experience for blasting vibration damage has been poor. This coverage is excluded from the Comprehensive General Liability (CGL) policy. To obtain this coverage, the policyholder must meet additional criteria and an additional premium must be paid. The risk management process offers the explosives user a technique for minimizing the risk of complaints and vibration damage claims on his insurance program and his cash flow. Case histories indicate that the vibration damage claims expense may be a lower risk than the risk of interference with production and cash flow. An annotated bibliography on risk management and defense of vibration damage claims is provided.

Jan 1, 1978

By Bob de Raadt

The main problem in blasting a fly-over spanning a main road is the brief time available for blasting and the removal of the debris, in order to minimize the ensuing traffic disruption in the public highway below. The blasting plan is consequently based on an extreme "time is money" concept, in which speed and public safety are predominant factors. This paper discusses reliable blasting parameters for this type of demolition.

Jan 1, 1984

By Ruilin Yang

Kinematic approach of blast modeling refers to using the velocity, strain, or displacement as controlling parameters to model blasting, rather than the stress and the material constitutive relations. The rock stiffness or constitutive relations is very hard or impossible to obtain due to the complexity of the rock mass property.

Feb 1, 2020

By Joshua Hoffman, William Chad Wedding, Braden Lusk

The emergence of electronic detonators as viable products for use in production mine blasting has enabled mining professionals to rethink the traditional blast design methodologies that pertain to timing. In many ways, electronic detonators can allow great advances in productivity, cost effectiveness, fragmentation, and safety. There are a number of commercially available systems that enable users to program delay times, usually in one-millisecond intervals, according to design decisions. While manufacturers have performed internal studies pertaining to the accuracy of these systems, an independent study quantifying the accuracy of the systems has not been completed to date. The mining industry is in the business of production and any quality control endeavors to independently confirm the accuracy studies performed by the manufacturers would only detract from their bottom lines. Furthermore, limited information is available concerning the accuracy of modern pyrotechnic delay based detonators. In 1985, the Bureau of mines completed a study of three manufacturers’ electric millisecond delay detonators (Bajpayee, 1985). This was the most recent extensive independent study performed on detonators, which unitized pyrotechnic delays, from numerous manufacturers. Advances in the manufacturing process for pyrotechnic delays may have increased the accuracy of detonators using these technologies in recent years. It is commonly accepted that electronic detonators are more accurate than both shock tube type non-electric as well as electric detonators, but the relative accuracy was not objectively and adequately quantified.

Jan 1, 2011

By Jhon J. Silva Castro

Blast vibration records used in mining contain unwanted information in the form of noise due to long-period drifts, background noise, and noise due to the conversion of the analogue signal to a digital signal. When recorded signals from blasting are used to find other physical variables, such as going from particle velocity to acceleration or displacement, the additional information in the vibration signal can result in inaccuracies in the estimation of the peak values and more dramatically, the results in displacement or acceleration can be nonzero near the end of the record. There are different proposed methods to clean or filter the unwanted information from the signal. All of the methods are based on finding the best fit of the record average value (baseline) and then subtracting from the record under analysis to produce the desirable adjustment. Different criteria and functions are used to define the best fit. The function to use will depend on the shape of the record average values. The main characteristic of the baseline function is that it represents a low frequency wave. Such a low frequency wave can be a periodic function or a polynomial expression of nth order. According to the order of the polynomial expression, the baseline correction can be linear, parabolic or high order. In this document the detailed procedure and the results for the baseline correction of a blast vibration record using a periodic function and a polynomial expression of different order is presented. The results show that the drift problem when displacement is calculate using velocity records increases with the increase of the distance from the blast.

Jan 1, 2015

By J. Silva, M. Kotraba, F. Pontanilla

Blasting is the application of highly complex science that, in some cases, could be viewed as an art. Many variables are involved in a blast, including geology, pattern design, timing and firing sequence, and explosives selection. Assuming that better results can be achieved by only increasing the powder factor is inaccurate. The Drill-to-Mill (D2M) concept has been in the mining industry for over two decades. The D2M approach is commonly viewed in an oversimplified manner, assuming that by simply increasing drilling and the amount of explosives used (both of which add operational costs), the downstream value will be created. An optimized D2M initiative should combine the smart application of explosives at the beginning of the mining process, matching the dynamic properties of the rock to the explosive selected to improve the efficiency of the energy created by the explosive to the rock mass being blasted, and to bring benefits to the mining operation across the entire mining and processing value-chain. This paper reviews the principles behind matching the shock impedance of the rock and the explosive and compares the traditional use of explosives versus the smart application for two hypothetical blasts.

Jan 1, 2024

By Stanley L. Lippincott

A number of Federal and State agencies require formal training for blasters. Federal agencies often specify the need for initial training involving all job responsibilities as well as periodic refresher training to assure adherence to current operating procedures. failure to provide and document such training can result in substantial penalties.

Jan 1, 1995

By J L. Jethwa, A G. Gaithankar

The paper deals with a software method developed to design the optimum blast parameters for tunnels and mine roadways for a given set of geo-mining condition without any major discontinuity. The application of the software is presently limited to 8 D-ahaped excavation where inclined hole cut or four-section parallel cut is used with smooth blasting technique.

Jan 1, 1993

By Michael Wieland

Three laboratory tests were developed for rating the wave-impact ruggedness of cap-sensitive explosives that are used for blasting in underground coal mines. Destructible pipe fixtures, called simulators, reproduce the shock wave or rift compression registered during the cross-hole wave interactions. The rift-compression fixture was modified to render quasi-static desensitization, when utilized with a remote air supply. Waves that were recorded near charge explosions show narrow pulses resembling underwater shock waves, followed by wide, weak humps, called rift compressions.

Jan 1, 1996

By Jack Eloranta

Proper selection of stemming has a profound effect on blast performance. This paper describes several methods of evaluating stemming performance in 16-inch blastholes. Tests are done on stemming ranging in size from nominal 1/4" crushed rock up to railroad ballast size rock (2 1/2" > diameter < 3/4"). Concrete plugs (both pre-cast and poured) are evaluated as well as air decking.

Jan 1, 1994

By T. N. Singh, Vasudev Singh

To explore and exploit the natural resources like oil, gas, economic mineral water drilling is still considered to be the reliable and economical method. When a drill bit penetrates the rock mass either by percussion or by rotary and may be some times a combination generates stress and thrust on the rock mass as well as on the drill bit. The strength and hardness of the rock govern the life of the drill bit and its runnage. Physico- Mechanical properties of rocks have great influence on drillability. It is observed that higher the strength of rock, reduce the life of the drill bit while drilling, ultimately decreases the drillability. An attempt has been made in the present paper to establish relation among various physicomechanical properties i.e. uniaxial compression strength, tensile strength, shear strength, Schmidt hardness and abrasivity with drillability of different rock types. The specific energy of each rock type has been calculated using micro-bit drilling. The rocks from different lithological succession were collected. The rock specimens were prepared according to the norms of International society of Rock Mechanics (ISRM).

Jan 1, 2008

By Hike Humphreys, Geoff Baldwin

A project aimed at blast optimisation for large open pit coal mines is utilising blast monitoring and analysis techniques, advanced dragline monitoring equipment, and blast simulation software, to assess the major controlling factors affecting both blast performance and subsequent dragline productivity. This has involved collaborative work between the explosives supplier, mine operator, monitoring equipment manufacturer, and a mining research organisation.

Jan 1, 1994