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By Dale Preece, Stephen Chung, D. Scott Scovira

The DMC_BLAST (Distinct Motion Code) has been developed to model rock motion and displacement during the gas expansion phase after the detonation of an explosive in a borehole. Recently, a designated delay firing order algorithm was written into the DMC_BLAST code. The model can now be used to analyze rock mass displacement for a V-cut, center opening, or sinking cut initiation sequences. This new feature allows the investigation of the effects of delay firing order on rock displacement when blasting complex inter-bedded and ore-waste structures. The model provides important ground movement and mixing indicators for dilution control in surface gold mining relative to the initiation sequences employed. Echelon blasts as compared to center opening type blasts show differences in their internal muckpile displacement. These displacement differences can be important to operations that mine narrow strike driven ore bodies. The model also has applications to through coal seam blasting and demonstrates that down-dip blasting is a better alternative than up-dip blasting. There is less disturbance to the dipping coal seam and less mixing of the rock and the coal.

Jan 1, 2000

By Jonathan D. Aubertin

The unique nature of rock salt blasting is compared to traditional hard rock practices. Rock salt geomechanical nature is discussed in the context of rock blasting events. A cratering mechanism prevalent in soft rocks is presented and exemplified through a series of single hole blast tests performed in salt deposits.

Feb 1, 2020

By Steve Dillingham

With the millennium fever all but faded, we look to a new century filled with awe and excitement. We step forward in time, marveling over the achievements of the 20th century and wondering what the next 100 years could possibly bring. Will there ever be another time that produces such technological advances, economic progress or social changes? Keeping pace with the awesome accomplishments of the past century has not been an easy task and we must prepare ourselves for the possibilities of the future. Take, blasting safety for instance. We all know that safety is personal - a culture - promulgated not only by the company by which you are employed, but, by a sense of your own personal responsibility that must constantly be reinforced through awareness, training, and discipline. Great strides have been made in blasting safety since its crude beginnings, however, safety consciousness becomes even more important as technological advances and scientific progress are made in the coming years. It all begins with a positive safety attitude where every employee habitually examines each situation encountered, identifies potential hazards, and takes precautions to avoid those hazards.

Jan 1, 2002

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Feb 6, 2023

By M. Syafiq Isnaya, Rahma Norfaeda, Slamet Rachman Jaka

This paper is about project improvement to maximize energy distribution while ensuring beneficial blast results (reduce boulder condition). The main problem is how to manage complex lithology conditions related to detonation propagation in energy distribution control.

Feb 1, 2020

By Joe Sr Strobbe

In 1933 the Cobre Mining Company re-opened the 32-year-old UV Industry Mine, which is located in a scenic canyon near Silver City, New Mexico. The site location is shown in Figure 1. Current mineral extractions are copper and magnetite; both extractions similar to those mined many years ago. Copper is extracted from chalcopyrite imbedded in the host rock of massive limestone deposits and magnetite, an iron ore, is a by-product of the same extraction process.

Jan 1, 1998

By Blenda Lopes, Rodolfo Matias, Vagner Paixão, Vinicius Leão VALE, Edivarde Sousa

Seismography is an extremely important subject in the context of rock blasting, especially in the current scenario, which involves the need for increased controls due to the growth of urban areas near open-pit mining operations. Worldwide, communities are becoming increasingly aware of the environmental and social impacts associated with mining activities. Therefore, maintaining good relationships with these stakeholders is essential to preserve the social license to operate and to comply with current legislation. This situation is exemplified in an open-pit iron mine near the capital of Minas Gerais, Brazil, where the community is located less than 40 meters from the pit boundaries. Blasting activities within the mining area occur at distances less than 500 meters from the nearest community, making continuous seismograph monitoring necessary to ensure that operational conditions are maintained without compromising exploitation efficiency. The threshold for peak particle velocity, according to Brazilian Standard 9653:2018 by ABNT, is 15 mm/s at frequencies around 4 Hz. However, even though the peak particle velocity commonly registered was inferior to 3 mm/s, there were still complaints from nearby residents regarding human discomfort. To further reduce vibration levels, a study was conducted to implement a new blast design, considering factors such as reducing bench height, altering the hole delays, maintaining the maximum charge per delay, and adjusting the drilling pattern without negatively affecting rock fragmentation quality. Following the implementation of the revised blasting parameters, seismographic measurements in the region decreased to below 0.6 mm/s. This significant reduction in ground vibrations contributed to minimizing community disturbances and fostering a more positive relationship between the company and its surrounding residents.

Jan 26, 2026

By Alejandro Berrios, Matheus DaSilva, Erick Siqueira

Vazante mine is an underground polymetallic mine that produces zinc, lead, and silver, which belongs to Nexa Resources in Minas Gerais, Brazil. The mine, a sublevel stope underground mine, mainly applies two subvariants: VRM – Vertical Retreat Mining and Open Stope. In a specific place of the mine, the geology allowed the design of a production stope with larger dimensions than the standard stopes, commonly called Super Stope. At this place, the plan was to apply both sublevel variants simultaneously. This mining block comprises rings in two different levels, with access by two ore drives on each level; the dimensions would be approximately 50 meters high, 50 meters long, and 35 meters wide. Opening the Free Face to mine the whole Stope was a challenge due to operational issues, such as hazard risks from loading over void space, exposure to uncontained places, and the impossibility of implementing the optimal blast sequence. Wireless blasting initiators have gained popularity recently due to their convenience, safety, and efficiency. This initiation system was applied to preload all the rings required to open the Free Face, ensuring a safe and optimal blast sequence. Wireless initiation prevented hazard risks, enhanced the blast sequence to guarantee the required void space, and optimized the equipment's operational cycle. The blast crew carried out the activity without exposure to the risk of loading over void space. The wireless detonators also avoided after-blast activities, which were required to provide secure access to the blast crew, optimizing the operational cycle.

Jan 21, 2025

By M. Szumny, P. Mertuszka, K. Fuławka

Multi-face destress blasting is the basic method of reducing rock bursts hazard in Polish copper mines. Blasting operations of this type are carried out regularly, twice a day in order to minimize the geomechanical threat while maintaining high extraction efficiency. Unfortunately, the assessment of the effectiveness of this type of work until recently was based solely on determining whether a given destress blasting triggered a seismic tremor or not. Information on the characteristics of seismic waves generated by blasting has so far been omitted in analyzes of this type. The lack of reliable knowledge about the generated seismic effect makes the introduction of constructive corrective actions impossible, which in turn significantly reduces the triggering potential of conducted destress blasting. This study presents the results of comprehensive work aimed at increasing the effectiveness of active rock burst prevention in Lubin underground copper mine. For this purpose, an innovative system for continuous monitoring of seismic waves induced by multi-face blasting was developed, and a new method for seismic assessment of the effectiveness of the destress activities was developed. Based on the monitoring data and the comprehensive analysis of waveforms, the effectiveness of individual blasting operations was determined, and on this basis, modifications to the drilling and blasting patterns aimed at increasing the generated seismic effect were proposed. The use of innovative methods of monitoring and data analysis made it possible to increase the effectiveness of the conducted activities, in terms of the magnitude of seismic vibrations, up to 250%. It should be emphasized that the introduced modifications were aimed at increasing the effectiveness of blasting operations while maintaining the current level of costs. As a result, the proposed solution turned out to be highly effective, significantly affecting the safety of the work carried out in Polish copper mines. Thus the proposed approach is planned to be implemented in other Polish copper mines belonging to KGHM in the near future

Jan 1, 2024

By Dale S. Preece

A Discrete element computer program named DMC (Distinct Motion Code) has been developed for modeling rock blasting. This program employs explicit time integration and uses spherical or cylindrical elements which are represented as circles in 2-D. DMC calculations have been compared with measurements on bench blasts in the field with relatively good comparison. Structural geology and joint sets have a significant impact on any blast and DMC has not, until now, included these effects. This paper discusses a recently added DMC capability for treating joints and bedding planes in bench blast simulations.

Jan 1, 1995

By Craig Adams, William Poe

Introduction The United States Department of the Interior, Minerals Management Service (MMS) is mandated under the Outer Continental Shelf Lands Act (OCSL A) and the Energy Policy Act of 2005 to oversee leasing, exploration, development, and production of mineral and renewable energy resources on the Outer Continental Shelf (OCS). Under these authorities, MMS is responsible for permitting and overseeing an array of offshore operations; some of which involve the underwater detonation of explosive charges. Explosives are most critical for their use in the severance of bottom-founded piles and well components during the decommissioning of OCS platforms and well abandonment work.

Jan 1, 2011

By Mathias Jern, Ruilin Yang

A blast vibration model has been developed that simulates effects of almost all blast design parameters on the blast vibration peak particle velocity (PPV) from a production blast with multiple blastholes at a given point of interest in the rock. The velocity of detonation (VoD), initiation points, explosive types (density, VoD, energy), charge decoupling, and decking in each blasthole are simulated along with other blast design parameters. The information from signature hole blast vibration and the blast design are the input to the model. The model can be used to assess blast damage in proximity of blastholes as well as far field vibration PPV.

Jan 1, 2019

By Robert J. Nothnagle, Kristen Franz Begor, Rodney W. Sutch

Recovery of contaminated groundwater in a fractured bedrock system presents some unique problems. Typically, the most common problem occurs from the inability to adequately characterize the discrete fractures through which contaminants may be migrating. Without adequate characterization, difficulties arise in properly positioning recovery wells and verifying the performance of the system. To overcome these difficulties at a site in Upstate New York, an innovative approach was developed involving the creation of an artificial fracture zone through controlled blasting to intercept contaminated groundwater flow.

Jan 1, 1988

By Hans Florin

This paper describes the modification of a nonelectric detonator which is ignited by a signal tubing. The heart of the new detonator lies in a so-called ignition transmitting element. The construction of the transmitting element is such that the detonator remains closed even after the signal tube has functioned. Due to the sealing of the delay element, this nonelectric detonator achieves the same accurate delay timing as high tech delay electric detonators and will not fail due to a sudden pressure loss.

Jan 1, 1988

By Gungor Tuncer, Ali Kahriman, Abdulkadir Karadogan, Simav Bargu, Savas Gorgun, Derya Kucukbrtem, Esat Tansev

Although many research studies had been carried out in the past in order to eliminate environmental issues produced from blasting unfortunately a general approach or formula has not been established yet because of the complexity of the matter. In addition to the wave and ground motion characteristics, the complexity of blasting parameters and site factors restrict the developing of a general criterion. So experimental site-specific studies should be still done in order to predict and control blasting effects.

Jan 1, 2002

By R W. Givens

Comparison tests were performed on 6 emulsion concentrates, 3 microballoon sensitized emulsion concentrates, and 2 water gel concentrates from 8 different sources with ANFO used as a control standard. Variables measured include density, detonation, velocity, detonation pressure, calculated borehole pressure, viscosity, and lead cylinder deformation for blends of 15%, 30%, and 45% concentrate and AN/ANFO blends. Comparative results are presented for detonation velocity vs. deformation, and percentage of inherent air vs. deformation for these blends. It was hoped that these tests would serve as a tool to facilitate the comparison of different manufacturer's concentrates in AN/ANFO blends for equivalent performance characteristics and to help evaluate these products on an equal basis for bid solicitation purposes.

Jan 1, 1990

By Neal Lee

Reduced relief horizontally means an increase in energy expended vertically into the rock surrounding the stemming column, and potentially through the stemming column. The vast majority of holes in any surface blasting operation are afforded two horizontal relief faces at the moment of firing, whether by existing relief faces in front of and to one side, or previously blasted hole(s) in front of and to one side of the holes in question. When the energy expended in any hole on the blast pattern has less than two Horizontal Relief Planes or faces (referred to moving forward here as “HRPs”) available to it at the moment of firing, a higher percentage of the available energy is directed vertically. In the analysis of recorded videos by the author, one will note the fact that stemming ejection/flyrock is observed to a much greater degree from the center of almost all patterns when they are timed to “pull out of the middle” (“box cut" timed patterns). This is because the first hole to fire in each row has only one Horizontal Relief Plane, which significantly decreases horizontal avenue for energy release for these holes. This of course results in an increase in the amount of energy expended vertically. This paper proposes a novel methodology to modify the stemming to better use the explosives energy of each hole, while controlling side effects such as flyrock and airblast.

Feb 6, 2023

By M J. Ball, R Watt

ICI has developed a new electrical shotfiring system which has markedly improved safety features and operational advantages over existing initiating systems. The development of the 'Magnadet' Electric Detonator and the related product 'Magna' Primer were described in a paper presented at the 1981 S.E.E. Annual Conference. Since then the system has been adopted in many different applications and conditions around the world. The present paper describes these applications, the experience gained and the more recent developments which have taken place.

Jan 1, 1982

By N K. Jain

"The idea of writing this article is to give correct picture about the technique in blastingindustries based on the safety aspect, basically without effecting the results thereof.Like many other sciences, blasting is rapidly advancing and research scientists are dailycreating new devices which are very reliable and efficient.The theory of explosion and all the respective changes caused by the explosives takingplace during the detonation has been brought up to the level enabling a mathematicalexpression of detonation characteristics even in comparative complex cases."

Jan 1, 1993

By Emily Johnson, Catherine Johnson, Ben Sonpon, Kelly Williams

The effect of length to diameter of the detonator is compared using Ansys/Autodyn 2-D simulations, the results of which are validated experimentally. It was found that higher pressure comes with a larger diameter, because it will result in more explosive energy being allocated out the end of the detonator.

Feb 1, 2020