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This is the story of a blast - not a large blast by todays standards as it only involved a total of approximately 50 cubic yards of rock. Nor did this blast involve any new or revolutionary blasting technique or require involved analysis or the applications of rock mechanics theories. Instead, it was a blast that involved the tried-and-true principles of good blasting: precise alignment of blastholes; selection of explosives and detonators designed for the conditions encountered; extreme care in loading and hooking up and the use of several ingenious devices and techniques to achieve the proper loading and firing of the blast

Jan 1, 1976

By Alan R. Cameron, Alastair C. Torrance

An explosives underwater test facility has been established and commissioned in the Hunter Valley, New South Wales, Australia which allows the measurement of the actual shock and gas energies of the explosive

Jan 1, 1990

By David E. Siskind

In the period 1989 to 1994, the U.S. Bureau of Mines assisted the Office of Surface Mining, Reclamation and Enforcement (OSM) in studying a high-complaint situation near an active surface coal mine. As part of a review for its project report, the Bureau had to address issues on the adequacy of the safe blasting criteria and analysis procedures in its 1980 report RI 8507, Structure Response and Damage Produced by Ground Vibration From Surface Mine Blasting.

Jan 1, 1996

By Kenneth Faroni, Catherine Aimone-Martin, Thomas Gelormino

A blasting improvement program began in 1985 at two traprock quarries in Connecticut to reduce the levels of ground motions and airblast measured at residential structures surrounding the operations. The quarries are situated within town limits, adjacent to a number of historical and other structures. Although blasting vibration amplitudes were found to be far below those that could produce cosmetic defects in structures, they were perceived to be the cause of structural defects observed by homeowners. Based on a comprehensive * review of blasting practices in place during1985, an extensive vibration monitoring program was implemented. The initial study included the instrumentation of selected residential structures to record and analyze strains imposed within structures from quarry blasting, environmental changes, and from daily household activities. A comparison of the results was made with the results reported by the U.S. Bureau of Mines in 1980. The highest strain imposed in drywall from blasting (13 J_I strain) was 12% and 1% of the highest strain levels recorded for normal household activities and temperature changes, respectively. The present philosophy in production blasting is to attempt to keep vibration amplitudes as low as practical by implementing state-of-art blasting control techniques. Currently, blasting seismographs are placed in a circular manner around each quarry, providing production blast vibration records for 360 degrees of coverage at distances of 2500 to 4000 ft. from blasting operations. Seismograph and production blast records are analyzed each year and become part of a Blasting Improvement Plan submitted to the local zoning commission as part of the annual operating permit process. This paper summarizes the results of previous vibration monitoring programs and outlines the modifications made to blasting practices to minimize the levels of ground motions and airblasts. The public relations efforts and standard corporate procedures used by company personnel to address all blast related complaints and alleged damage claims since 1985 are also discussed.

Jan 1, 2000

By R. K. Wharton, G. H. Pickering

The paper reviews the explosives products that have been certified by the different Explosives Notified Bodies for sale in European Union countries. The development of harmonised standards for explosives is also discussed as are recent developments relating to certification and a possible forthcoming Directive on pyrotechnic articles.Copyright

Jan 1, 2004

By Sehoon Lee, Duhwoe Jung, Eunsu Cha, Kyeonghwan Jeong

This case study presents the effectiveness of underground rock blasting to facilitate the trench cut in the hard rock layer using a conventional trench cutter for the construction of a diaphragm wall. Rock blastings are pre-performed up to the scheduled depth and then the fragmented rocks can be easily cut using a conventional trench cutter. Two trial underground rock blastings have been performed and the effectiveness of pre-blasting is presented in terms of a cutting rate, a loss of cutter heads and an amount of overbreak. Based on the results obtained from the trial underground rock blastings, the following conclusions can be appropriate: 1) A pre-blasting of hard rock layer located in depth can help to overcome the limitation of the trench cut using a conventional trench cutter. If the hard rock layer is fragmented after blasting, the fragmented rocks can be easily cut using a conventional trench cutter, 2) The speed of cutting works was accelerated and the loss of cutter heads was significantly reduced in the sections where the blastings were applied prior to cutting. 3) The amount of overbreak, expressed in terms of the amount of poured concrete, can be reduced to some extent. However, the location of blast holes in the trench can also contribute to the amount of overbreak. The closer the location of blast holes to the edge of the trench, the more extensive fractured and cracked zone can be formed on the face of the trench. This can increase the amount of overbreak if the trench is left empty for a while.

Jan 1, 2000

By William C. Burkle

In this paper, the author has cited essential areas in which the explosives engineer can assist the mine manager in his planning of an entirely new operation or in a major expansion of an existing facility.

Jan 1, 1990

By Bill Bauet, John Anderson

There are always security concerns when explosives are transported and stored, and these concerns are intensified in peacekeeping operations where explosives could fall into the wrong hands. MREL Specialty Explosive Products Limited has developed FIXORTM, a new approach to neutralizing landmines and unexploded ordnance (UXO). The product consists of two precursors: a flammable liquid in one plastic container and a totally inert powder in another; neither of these precursors is classified as explosives. Both precursors are approved for transport by land, sea and commercial passenger airfreight. The precursors are mixed to form an explosive immediately prior to placement next to the UXO or landmine. Initiation is by blasting cap or detonating cord.

Jan 1, 2001

By Zahra Hosseini, S. Hassan Khoshroo, Mohsen Amirrahmat

The Sarcheshmeh Copper mine will be developing its open-pit in order to reach to the remaining ore in the deposit. One of the problems regarding the development plan is the ore handling system from the pit. After its development, the pit depth and its daily production will be increased. Therefore, the present transportation system (shovel and trucks) can no longer be used efficiently. It is necessary to use a new system that can reduce transportation costs and handle the new amount of blasted material at the same time. Studies show that an in-pit crusher and conveyor belt is the most suitable system that could be used in this situation. One of disadvantages of the conveyor belt, however, is its limitation in the particle sizes that it could carry. Consequently, size distribution resulting from the fragmentation process is an important parameter in choosing an efficient conveyor belt system. The size distribution of the fragmentation process also affects the operations following blasting. The determination of this parameter allows the optimization of blast design and explosives. Hence, during this project, the size distribution of blast fragmentation in the different types of ore at the Sarcheshmeh mine was determined by the image analysis technique. Numerous digital pictures were captured of the different blasted faces to prepare a representative sample of each kind of rock. They were then analyzed using the GoldSize image analysis software. Results show that fragmentation in the blasted rock is relatively high. It is therefore expected that an appropriate conveyor belt could be selected for further developing the open-pit mine at Sarcheshmeh.

Jan 1, 2004

By Alain Blanchier

Because in Europe and in many other countries as well every new project (quarry, mine, public work) needs a risk estimation to prove its feasibility, a model to estimate flyrock risks became necessary. This paper presents the basic hypothesis which should underlay such a model to estimate statistical flyrocks range for not only some single blasts but a whole project and in particular the way to take into account rockmass or blast pattern parameters variability. It describes a first usable quantitative flyrock model based on the characteristics of the blasting plan and of the generic laws utilised in casting and selective blasting operations and on a statistical approach of rockmass. In a second step, this paper discuss an approach of risks estimation compared to the classical one used in pyrotechnics studies for explosive magazine risks assessment.

Jan 1, 2013

By Kfw Eick

The paper describes the use of the Nonel millisecond delay blasting system in narrow, deep, tabular ore bodies and briefly describes the standard stoping method as used on Harmony Gold Mine and compares this with the new Nonel short panel system.

Jan 1, 1990

By Kurt Oakes, John Williams

Placer Dome, US operates the Bald Mountain Mine. The Bald Mountain Mine is a surface operation located in remote northwestern White Pine County in east-central Nevada, approximately midway between Elko and Ely. The mine is in the Newark Valley along the southwestern flank of Bald Mountain a part of the Ruby Mountain range, at an approximate elevation of 7,500 ft (2,286 m). The geology at the Bald Mountain Mine is highly altered, both mineralogically, and structurally. Highwall stability and control have long been an issue at the operation, due largely to the varying geologic conditions. In some blasts as many as seven distinct geologic unconformities exist. These unconformities affect both final high wall integrities, as well as blast fragmentation characteristics. A 60 million ton (54.5 million tonnes) layback expansion of the existing “Top Pit” as well as development of a new satellite pit, “Sage Flats”, is being undertaken. Design final highwall pit slopes have been steepened from the traditional 47º to 55º in order to reduce overall ore-to-waste ratios, thereby improving economic viability for the expansion over the 4.5 year life of the project. With the increased usage of electronic detonators throughout the mining industry, mine operations staff, as well as representatives from the mines explosive supplier felt that an evaluation program incorporating electronic detonators would be warranted. The areas of focus for this evaluation would be resultant highwall pre-split integrities, peak particle velocity measurements (both near field and far field), frequency measurements, loader productivity, and visual interpretation of the results. The mine incorporates 25 ft (7.6 m) benches and uses separate trim blasts in conjunction with production blasts in order to reduce blast effects along final highwalls. Hole diameters in production blasts are 7? ” (200 mm). Typical production blast patterns are 18 ft x 18 ft (5.5 m x 5.5 m), drilled in a square pattern configuration. Shot sizes vary greatly, ranging from 200 holes to as many as 800. Bulk low percentage ANFO/emulsion blends are utilized as the redominant blasting agent. Non-electric dual delay detonators (25 ms/500 ms), with non-electric surface delays are the initiation system utilized in production blasts. Typical production blast design

Jan 1, 2004

By C James Dahn

A new generation of high performance and high density ammonium nitrate prills have been developed. These cycled "prills" offer significant improvement in ANFO mixing time, detonation velocity performance, and heaving capabilities. In addition, their safety characteristics are better than standard ANFO explosives.

Jan 1, 1980

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 A K. Raina, P B. Chourdhury

Flyrock is the unwanted throw of rock fragments to excessive distances in opencast blasting. The incidence is relative in nature incorporating the distance of objects of concern like structures within and outside the mine, equipment within the mine & near the blast and persons within and off the mine. Several attempts to predict and defi ne fl yrock made worldwide could not address the problem since the phenomenon is not a regular feature in blasting. This probabilistic nature of fl yrock allows for risk calculation. CIMFR, India developed a Factor of Safety based risk criterion (10, 14) for evaluation of throw/ fl yrock in opencast mines that incorporates all the above in terms of distance and allowable limit of throw – which in turn determines the risk. The criterion provides the blaster a tool for mathematical evaluation of fl yrock risk in terms of a Factor of Safety and threat ratio (defi ned for the 1st time), thereby enhancing confidence when blasting. The method is easy to use and has been applied to several mines in India and the results are signifi cant. This paper details the evolution of the concept and its application in three limestone mines of India and the results obtained. The application of the method for defi ning a fl exible danger zone is also discussed.

Jan 1, 2008

By Roger Keller, Jason Ryan

A number of studies have evaluated excavation methods for the construction of subsurface facilities for a potential deep geologic repository for the disposal of nuclear waste at Yucca Mountain, NV. Many of these studies suggest that where TBM (tunnel boring machine) methods are not applicable and alternative mechanical excavation methods can not efficiently excavate harder rock drill and blast methods may be the most efficient means of excavation. However, a number of concerns regarding drill and blast applications have been raised in these evaluations, most notably the affects of blasting on the surrounding perimeter, as isolation of the waste by the natural barrier of the surrounding rock is a key element in the concept of a deep geologic repository.

Jan 1, 2001

By Kenneth K. Eltschlager, Richard R. Brochu

At the International Society of Explosives Engineers Annual Conference held in Nashville, Tennessee in February 1995, a Seismograph Standards Committee was established. The purpose of this committee was to develop objective performance specifications for vibration measurement instrumentation and field use practices. It was also understood that due to geology, temperature, and moisture in the soils, it is not possible to design and build an instrument to give results which are absolutely comparable for ground vibration. It was, however, considered essential to standardize instrumentation by which vibration can be measured under closely defined conditions so that results obtained by users of seismographs are always the same within stated tolerances.

Jan 1, 1999

By David Yanez

The hydroelectric project "El Cajón" is currently under construction in the state of Nayarit, on the Santiago River, in western Mexico. This project is comprised of a Concrete Face Rockfill Dam (CFRD) with a rockfill necessity of 10,5 million cubic meters and it reaches a height of 188 m. The generation equipment includes two turbines with a total installed capacity of 750 MW.

Jan 1, 2006

By Jim Hall, Denis Rickman, Jon Windham, John Ehrgott, Stephen Akers, Byron Armstrong

With the growing concerns about terrorism world-wide, numerous agencies conduct experiments to investigate the effects of terrorist vehicle bombs. In many cases, the vehicle bomb of interest utilizes some form of ammonium nitrate/fuel oil (ANFO) as the explosive source. Due to the high cost of fullscale testing, it is advantageous to conduct at least some vehicle bomb experiments at reduced scale. Extensive testing has shown that ANFO is a non-ideal explosive, and its explosive output does not scale reliably at explosive masses below approximately 400 lb (182 kg). Most scale-model testing requires explosive masses 1 to 5 orders of magnitude smaller. Thus, scale-model testing is typically conducted with “ideal” explosives, such as composition C-4, which perform in a scalable manner at virtually any charge mass. The utilization of an ideal explosive to model ANFO requires the existence of an accurate means of equating the performance of the two explosives. The airblast equivalence of C-4 and ANFO has been well established. However, the cratering equivalence of these explosives is not thoroughly quantified. This is especially true for the case of an above-ground detonation, which is precisely the scenario of interest in vehicle bomb studies. A study has been conducted to better define the cratering equivalence of C-4 and ANFO for above-ground detonations. This paper presents a discussion of results from this research.

Jan 1, 2008

By Peter P. Harvey

The Nonel Primadet is a non-electric delay blasting cap initiation system. The most recent field application of the system in the Southwest has been at the Magma Superior Mine, Superior, Arizona.

Jan 1, 1978