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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

By S Lukovic, Robert Briton, Calvin J. Konya

Investigators have reported that charges which are decoupled from the borehole wall produce different fragmentation then those which are fully coupled. The difference in effect could be as a result of energy doss during transmission across the air gap or it could be due to the change in detonation characteristics of the explosive as a result of the change in confinement on the charge during detonation. In order to better understand the phenomena of decoupling, a research project was conducted at the United States Bureau of Mines Station, near Pittsburgh, Pennsylvania. It was decided to use shock and bubble energy tests along with simultaneous velocity measurement to determine the mechanics of decoupling and energy transmission. Two explosives were selected for the test, one dynamite and one water gel. Test results indicated that decoupling could both boost the total energy output of the explosive and that further decoupling would drop the energy output.

Jan 1, 1987

By Richard D. Love

Competition in the aggregate industry of the 90's will be an over increasing really. With this in mind a quarry manager should always be comparing new and innovative concepts to increase productivity and reduce operating costs. In this paper, the author will present a comprehensive history of a drilling and blasting program that achieves these results. By employing proven methods and implementing new concepts, this program was proven to be a success over a ten year period.

Jan 1, 1991

By Pierre Mousset-Jones, Geraint W. Harris, Robert Karlin, Jaak Daemen

In order to minimize the ore dilution induced by blast movement in surface mines it is necessary to quantify such movement. This will make it possible to more accurately locate the grade boundaries on the surface of a blasted rockpile prior to excavation. This paper describes the development and testing of a method to accurately measure the direction and magnitude of sub-surface blast movement. The technique involves the use of magnetic "radiometry, using a cesium vapor "radiometer and real-time differentially corrected, GPS system, to locate the post-blast position of magnetically enhanced target objects, whose pre-blast locations are known, without disturbance of the blasted rock. The objective is to design an accurate and efficient technique which can be integrated into a mines production cycle.

Jan 1, 1997

By Frank Lucca

This paper includes research and investigation into blast design and blast optimization for vibration control in municipal and tight blasting situations, where specifications were extremely stringent. The paper is written for the field blaster to understand and develop blast plans based on field conditions. The paper includes blast design considerations, utilizing seismograph arrays to check and predict vibration results, and problems encountered in vibration monitoring in extremely tight situations (0-20 feet). Blast vibration frequency, acceleration, peak particle velocities, and relative displacement are discussed with effects in the near and far fields and blast designs utilized to stay under limits. The paper also discusses using the latest in technology for blast design to control vibration. Equipment includes 2D and 3D laser profiling systems, digital video, fragmentation analysis, seismograph arrays, and borehole tracking devices. Other topics are discussed such as public relations, working with regulatory personnel, unions, and other project consultants, and the problems associated with municipal blasting situations, such as, flyrock and proximity of other personnel and equipment on the project.

Jan 1, 2004

By Walt Meglasson

"Developing technologies in demolition equipment and processes have produced a newsophistication within the demolition industry. Yet, with increasing frequency, owners,architects, engineers, and contractors reject out of hand one of the safest and most effectivetools in the demolition industry today, specifically the use of explosives and blastingtechniques in man_made structure removal. The use of explosives in any application mustbe considered as a tool, no more or less dangerous than any other type of tool, when usedproperly. Accordingly, importance must be attached to recognizing the skill, integrity, andcare of those who use it. Massive amounts of information and help are available to assistthe rock blaster, ranging from the practical to the highly theoretical, but very littleinformation exists to guide anyone considering unleashing the power of explosives instructural demolition blasting. The planning and work required to execute such projects iscomplex, and the recognition of the different applications explosives can be applied to isthe first step."

Jan 1, 1993

By Elaine Gorham-Bergeron

CAROM is a distinct element, dynamic code developed at Sandia National Laboratories to calculate the motion of rock fragments during blasting.[1] It has recently been improved to incorporate a mechanism for its elements to mimic non-circular rock fragments. With this option, elements stack and move in ways that are characteristic of irregular boulders of blasted rock. In bench geometry, CAROM has been used to examine the possibility of producing variations in muckpile shape due to variations in detonation-time delays between rows. Surprisingly, the shape of the muckpile was predicted to be insensitive to time delays between detonation of rows of explosive, except where the rock fracturing was affected by the time delays.

Jan 1, 1987

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 Dale S. Preece, J Paul Tidman, Stephen H. Chung

A discrete element computer program named DMC_BLAST (Distinct Motion Code) has been under development since 1987 for modeling rock blasting (Preece & Taylor, 1989). This program employs explicit time integration and uses spherical or cylindrical elements that are represented as circles in 2-D. DMC_BLAST calculations compare favorably with data from actual bench blasts (Preece et al, 1993).

Jan 1, 1997

By Robert B. Hopler

The Hercudet ? Nonelectric Delay Blasting Cap System has undergone significant changes since the last paper on the subject was presented at the 1978 S.E.E. Conference. The changes have been made to improve reliability of the blasting machine at low temperatures, and to improve efficiency and economy in usage in surface mining. The paper includes examples of the blast design process, details of use of the new in-hole connected cap, and delay patterns which have found use in quarrying and coal stripping.

Jan 1, 1980

By Dale S. Preece, J Paul Tidman, Stephen H. Chung

A discrete element computer program named DMC_BLAST (Distinct Motion Code) has been under development since 1987 for modeling rock blasting (Preece & Taylor, 1989). This program employs explicit time integration and uses spherical or cylindrical elements that are represented as circles in two dimensions (2-D). DMC_BLAST calculations compare favorably with data from actual bench blasts (Preece et al, 1993).

Jan 1, 1998

By Thomas C. Rube, T S. Bajpayee

The Bureau of Mines conducted research to determine the safe operating conditions for using recycled (used) lubricating oil from mining equipment as a partial replacement for diesel fuel to make ANFO-type blasting agents. The use of recycled oil (RO) saves energy, reduces oil imports, and reduces mining costs.

Jan 1, 1996

By Claude Cunningham

AEL’s Electronic Delay Detonators are in routine use and growing in both volume and breadth of application in Africa. This trend will continue and grow internationally owing to increasing pressure on rockbreaking operations to conform to sustainable development principles. A fundamental breakthrough has been achieved, bringing production blasting into line with technologies, which leverage performance through tight monitoring and control. When moving from pyrotechnic systems, benefits are normally realized without having to adopt different timing patterns, but significant additional benefits are realisable by using the flexibility and precision of the electronic units to enter windows of timing previously closed. The higher price and increased care needed are a worthwhile investment, enabling operations to cross the chasm to stronger revenues, but the system must be robust and suited to the application and personnel. Economic models are vital for keeping track of the potential and achieved benefits of these systems. Some resistance can be expected from those who stand to lose income as a result of the improved efficiencies.

Jan 1, 2004

By Dale S. Preece, Stephen H. Chung

"A discrete element computer program named DMC_BLAST (Distinct Motion Code) has been underdevelopment since 1987 for modeling rock blasting (Preece & Taylor, 1989). This program employsexplicit time integration and uses spherical or cylindrical elements that are represented as circles in two dimensions (2-D). DMC_BLAST calculations compare favorably with data from actual bench blasts (Preece et al, 1993b)."

Jan 1, 1999

By W. De Graaf, C. Mkumbo

Bulyanhulu Gold Mine Limited (BGML) commissioned a project of sinking a Bulk Air Cooling Shaft during its programme to improve the ventilation system on the mine. As part of this project, a ventilation drift had to be developed and holed into the Main Shaft at 4920 Level. AEL Mining Services (AEL) were requested to provide a technical solution, which included monitoring of blast induced vibrations and to design drilling and timing plans to ensure blasting activities on the vent drift were conducted without disrupting the main shaft’s infrastructure.

Jan 1, 2011

By Ery Wardhana, Fathur Rozaq, Jeff Averett, Nella Lubis, Carl Lager, Herry Saputra, Rudolf Sitorus, Relinda Sanistrya, Hormat Sinaga, Andhiko Maharjono

Efficient drill and blast operations are crucial for achieving optimal fragmentation, productivity, safety, and operational efficiency for the mining industry. However, conventional methods face significant challenges, including manual borehole marking and retrieval by survey teams, limited real-time data monitoring, excessive borehole collar deviation affecting blast quality, suboptimal drill productivity impacting person-hours and fuel usage, subjective judgment by drill operators on voids during drilling, and limitations in explosive charging design that do not match rock hardness. Rock hardness determination using lithological data from exploration models is often inaccurate due to the interpolation effect of wide drilling distances and depths, necessitating manual field verification using drill cuttings and historical blasting results. Furthermore, using single-density bulk emulsion throughout blast holes leads to suboptimal results due to varying rock properties. This study introduces an integrated approach that combines smart drilling technology with advanced emulsion technology to enhance drilling and blasting efficiency. The method utilizes smart drilling technology with GPS for precise borehole placement, Measure While Drilling (MWD) loggers, and real-time performance monitoring. Additionally, it integrates a smart Mobile Processing Unit (MPU) featuring a digital system and an automated gassing system (AGS). This setup allows for multiple emulsion densities within a single blast hole, customized to match the hardness index parameters determined from MWD data, addressing the challenges in drilling and blasting operations. The study evaluates the effectiveness of this innovative approach through comprehensive field trials and data analysis. While maintaining the digging rate according to production targets, key metrics such as drilling productivity, drilling accuracy, fuel consumption, powder factor, drilling and blasting cost, and fragmentation size were compared between conventional and new methods. Results showed a 56% increase in drilling accuracy, a 23% increase in penetration rate, a 19.6% increase in drilling productivity, and a 29% reduction in fuel consumption. This new method decreased the powder factor by 5.2%, impacting the drill & blast cost reduction by 2.3%. Moreover, fragmentation size improved by 12.8%, demonstrating the effectiveness of rock hardness-adjustable emulsion density in achieving better blast energy placement. In conclusion, integrating smart drilling and advanced emulsion technology significantly enhances drilling and blasting efficiency. This approach offers substantial cost savings and operational improvements, providing a strong rationale for adopting this innovative method in drilling and blasting activities.

Jan 21, 2025

By Sergio Segovia Parra, Victor Hernan Sheen Uriol

This contribution of the concept of mass blasting both closing and production allows breaking paradigms, to limit the number of tons to thunder. The areas of geotechnical different mining large mining companies worldwide and especially from the National Copper Corporation (CODELCO, Chile) has been declining volumes closing blasting and production, with the misconception to protect the end walls of the pit, before any geotechnical risks caused by various types of faults; especially the circular faults. A blasting of small tonnage can do more damage to a wall when it is not properly sequenced, leading to the coupling of the wave train and therefore the exponential damage in/s (peak particle velocity, PPV) on the wall of the Tagus. Blasting closing mass production and contribute technically and operationally in the dynamics of the following operations: loading, hauling, crushing, processing and preparation of the final product; eliminating delays to return to thunder small volumes where one must stop all mine equipment, incurring high costs and especially losing valuable time in the continuity of the following unit activities.

Jan 1, 2015

By Michael S. Wieland

This report discusses the U.S. Bureau of Mines research regarding the desensitization and malfunction of cap-sensitive explosives deployed in underground coal mines. Delay blasting in underground coal generates severe shock waves and rifting forces that fracture and heave coal. These dynamic interactions can damage other charges still remaining in the delay pattern. The debilitating impacts precipitate degrees of reduced charge performance ranging from misfires to weak detonations or out-of-sequence firings. Damaged charges react poorly, perform less useful work, and/or generate atypical fumes with higher toxicity.

Jan 1, 1993

By Charles E. Joachim, Christo V. Lunderman, Charles R. Wdch

The U.S. Army Engineer Waterways Experiment Station (WES) recently conducted a series of precision-scale water shock experiments which consisted of the detonation of several 8-gram, 10-gram, and 12-gram spherical explosive charges. The charges were fabricated from NAX 2000 Primasheet explosive and were center-detonated. Commercial tourmaline crystal water shock sensors were used to measure the induced pressure fields in the water. The measured water shock waveforms and related parameters from the precision-scale experiments were in general agreement with data from larger-scale experiments.

Jan 1, 1998

By Douglas R. Burns

Complying with SARA-Title III and the Emergency Planning and Community Right-To-Know Act as a Non-Manufacturing Facility. As of August 23, 1988 non-manufacturing facilities storing end using chemicals which require MSDS (Materia1 Safety Data Sheets) must fi1e with SERC (State Emergency Response Commission), the LEPC (Loca1 Emergency Planning Commission), and the loca1 Fire Department a list or copies of all MSDS sheets with the Tier I and Tier II forms completed.

Jan 1, 1989