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By Joseph Kennedy

How do terrorists and other criminal bombers acquire explosives to be used in an attack against U.S property and/or citizens? The Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) with nearly 40 years of investigating bombings and other explosives incidents, has learned that explosive materials intended to be used in criminal acts are obtained primarily by theft, clandestine manufacture or diversion.

Jan 1, 2010

By G Mendoza, L Taddei, C Robertson

It is a well-known industry fact that many mine sites around the globe experience blast holes that have elevated temperatures due to reactive ground, geochemical reactions, geomorphic reactions, sub level open fires, etc. It has been reported in many previous industry publications (White, Saputra et al) that elevated blast hole temperatures are a norm at many mine sites and are dealt with on an ongoing basis while the drill and blast process continues under elevated states of alert. The choice of explosives products including the type of detonator, primer, accessory, and bulk product all must be taken into consideration when loading blast holes where there is a known potential for elevated temperature conditions. It should also be noted that these elevated temperatures inside blast holes can be consistent throughout the blast hole length or vary in position within the blast hole depending on the mine conditions mentioned in the opening statement above. The risks associated with the loading of primers and bulk explosives in holes where elevated temperatures are present include: the ejection of the bulk explosives product, deflagration of the explosives during initiation of the blast or premature and uncontrolled initiation of a blast hole(s). This paper describes a unique and novel approach to the active monitoring of the temperature within blast holes with the application of electronic detonators with integrated temperature measuring (ITM) capabilities, deployed and demonstrated at a mine site in Mexico during January 2023 to March 2023. The deployment of ITM capable electronic detonators allows a user to monitor and record the real time temperature at multiple locations (e.g., toe, middle and collar) at each electronic detonator’s position within the blast hole, with the ability to react instantaneously to elevations in temperature reported. The measurement of the temperature can be for a single ITM electronic detonator, or simultaneous for an array of ITM electronic detonators, allowing for the potential for the data to be represented by a time/temperature/hole depth three-dimensional heat map. Changes in temperature at different borehole positions can vary, however, often the collar position is expected to be the most reactive due the combination of bulk explosive product and oxygen exposure, which can be confirmed with the application of the ITM electronic detonators. A mine site’s reaction to a measured elevated temperature within a blast hole can vary depending on the temperature measured and the change in temperature from the last measurement made. The study was found to produce real-time in-hole temperature information which was previously unobtainable without the introduction of another device. New and adaptive elevated temperature hole policies can be created and adapted proactively as real time information is received, leading to a safer mining operation.

Jan 21, 2025

Case histories in blasting show that Livingston's cratering technology has been applied successfully to blast designs with explosives having a charge length to diameter ratio not larger than 6. But the evaluation of experimental results such as the crater volume is tedious and sometimes impractical. A key analysis presented in the study shows that the optimum scaled volume relates well with the optimum scaled rupture limit, and the latter can be determined by means of high speed photography without excavating the blasted material. Through the studies of harvesting gypsum from a dried up settling pond the high speed photography approach has demonstrated to be effective for determining the optimum design for blasting plastic material.

Jan 1, 1987

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 Klaus G. Hinzen

Seismic observations offer the only possibility for remote sensing of physical processes like shock-front spreading, material crushing and ground movement. A better understanding of these processes will help to increase the economy of blasting. We developed a digital seismic monitoring system for research purposes. The system can simultaneously record up to 64 channels with a maximum sampling rate of 31 kHz per channel. A software package for rigorous analysis of blast induced seismic waves has been developed.

Jan 1, 1989

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 Abraham Lindo

Taboguilla is a small island located 10 miles outside the Panama Canal Pacific Entrance. In 2002 a fuel distribution facility was installed in order to supply fuel to vessels passing thru the canal. The current capacity of the tank farm is equivalent to 1,100,000 barrels. The demand for marine diesel at this location still exceeds the current capacity, thus an expansion project is currently underway to increase the available space for diesel tanks. There is a total of 800,000 cubic meters to be excavated in order to create the new space. 400,000 cubic meters of that total is basalt rock which will need to be blasted

Jan 1, 2011

By Gungor Tuncer, Ali Kahriman, Abdulkadir Karadogan, Umit Ozer

The environmental problems such as vibration, and air blast are often faced, and discussed on mining, quarrying, civil constructions, shaft-tunnel, pipeline, and dam operations where blasting is inevitable. It is necessary to establish national standards towards to minimize the environmental problems induced by blasting and judicial matters in our country as it is in USA, EU countries and the other developed countries. This necessity and the obligatory of accepting the European Union criteria for Turkey that has started the procedure of joining to EU emphasize the importance of this study. In other words, the establishment of a particular national standard related with this subject is inevitable for Turkey. This will be possible only by studying, applying scientific methods and techniques by the experts.

Jan 1, 2010

By R W. Givens

This paper presents blast casting design variables that have been developed and are currently being used at the High Power Energy mine in West Virginia. The shot specifications are summarized in Table I. The two active casting pits were designed with casting in mind and as a result are better designed and more efficient. About 55% of the overburden material is effectively cast and clean up is done by a bulldozer, front-end-loader, and trucks. This results in a 15X decrease in the cost of coal production.

Jan 1, 1988

By Guillermo Silva

A novel, ultra-low density explosive composition, particularly suited for wall control and other applications requiring customising of the explosive’s energy output, has been developed. Being reactive in nature, the low density explosive enables the controlled dilution of dry blasting agents from their nominal densities down to values slightly less than 0.10 g/cm3. The product has been detonated at densities of 0.07 g/cm3 in diameters as small as 50mm under confined conditions, using a 227 g (l/2 lb.) primer. Recorded velocities of detonation ranged between 1200 m/set and 2200 m/set for densities between 0.07 and 0.2 g/cm3. Theoretical velocities ranged from 1700 m/s to 2500 m/s for the same density range. The low density explosive was insensitive to initiation by a blasting cap which is a desirable feature for transportation purposes. Mixing of the product with ANFO has been accomplished with minimum segregation making it suitable for applications where reduction of pressures are necessary.

Jan 1, 2000

By Jorge Cárdenas, Diego Gamarra

In previous phases of the mine, a landslide resulted in several losses in production delays. The stability of slopes in a mining operation is critical for the sustainability of the operation, as they are exposed to vibrations and damage caused by blasting. Therefore, it is essential to implement controls and innovative technologies to reduce these vibrations levels. This study focuses on the application of low-energy emulsions with lower densities than conventional explosives, developed to reduce vibrations and the energy delivered to the rock mass adjacent to the near blast holes as a buffer row. Near field studies were carried out by embedding triaxial geophones. Vibrations were recorded, and mathematical models of vibration associated with different types of explosive mixtures were generated. This allowed us to determine the benefit of implementing low-density explosives in reducing vibrations compared to Heavy ANFO explosives. The application of low-energy explosives with densities ranging from 0.7 to 0.8 g/cm³ and Relative Bulk Strength (RBS) of 51-65 allows for a 40% reduction in vibrations compared to the detonation of Heavy ANFO explosives.

Jan 21, 2025

By Michael Karmis, Syed Muhammad Tariq, Zeshan Hyder

This paper analyzes the blast design for lime stone quarries of two major cement plants in Pakistan. The production blast of these quarries was resulting in excessive boulders production. At some instances, the rate of boulders production was approximately 10%-15% of the main production blast i.e. if a round of main blast gave around 4000 tons of material; almost 400 to 500 tons of that material was in the shape of massive boulders. This gave rise to increased operating costs requiring boulders collection, drilling and secondary blast.

Jan 1, 2012

By Michael Laing

Blasting regulation and restrictions are tougher today than ever before. When blasting in population centers, strict limitations are often placed on the environmental effects caused by blasting, more specifically vibration and overpressure. Blast-induced vibration can be a tricky thing to manage at times, but there are a variety of options at our disposal to help optimize and manage vibration. This paper focuses on the application of rudimentary signature hole analysis to optimize blasting vibration in localized areas surrounding a mine.

Jan 1, 2017

By Ricardo González Dumuihual, Carlos Scherpenisse

A monitoring campaign to record dynamic pressures generated by detonation of a single blasthole was implemented at Barrick Gold´s Pueblo Viejo Open Pit mine (PVDC), located in the Dominican Republic . Pressure amplitudes beyond the dynamic compressive strength of the electronic detonator´s capsules have the potential to damage these electronic devices, generating misfires along with all the associated risks and entailed safety implications. In most instances, misfires generated from high dynamic pressures are a direct consequence of drilling deviations resulting in blasthole distances smaller than originally designed.

Feb 1, 2020

By Adrian Moore, Bryan Goodwin, David Fales, David Lam

This paper describes the development of blasting protocols used to successfully create a 450m long blast fractured permeable trench in a basalt aquifer up to 20m thick, at a petrochemical facility in Australia, to enable the remediation of contaminated groundwater.

Jan 1, 2011

By Scott G. Giltner, Alex Schwenk

Blasting within 250 ft of a crusher was successfully executed through the application of electronic detonators, 3-D imagery, signature hole analysis, custom loading of blast holes. The blast was well contained, the vibrations were minimal, and there was no flyrock.

Feb 1, 2020

By Javier Illanes Pizarro, Gustavo Huerta Valer, Jorge Cárdenas Miranda

Bench stability is the basis of sustainability in an open pit mining operation. Taking care of the pit walls while maintaining fragmentation results can prove a challenge. In this study, technical proposals have been developed for extra hard rock mass (UCS>175MPa) with presence of unfavorable structural planes in high copper grade zones. The base case shows low compliance of fragmentation results and a significant loss in berm width, with over size boulders causing low primary crushing rates. Paradigms in current drill and blast design were overcome to improve fragmentation results and achieve objectives.

Feb 6, 2023

By Vitor Fonseca de Barcelos, Jair Carlos Koppe

Our society is experiencing a digital revolution. Technology is demonstrating its significant potential for mining industry. In this paper are presented the measured and estimated impacts of applying new technologies on blasting operations in a copper mine.

Feb 1, 2020

By Duane A. Houkom

Explosive demolition of concrete has been accepted as a safe and economical means of concrete removal for many years. I imagine that the early concrete blasters were experienced rock blasters who applied their knowledge to just another formation. Since a concrete foundation is generally located in a congested area, the owner is willing to accept the higher costs of mechanical removal,rather than promote "a new idea" to his management. This attitude is rapidly changing,making it possible to use the advantages of explosives in more congested locations.

Jan 1, 1982

By Sanjay Sengar, Nabiullah Pingua, Saurabh Sahay

In India, more than 80 percent of the total of 557 million metric ton coal production comes from open-cast mines involving large overburden removal with average 1:3.5 stripping ratio which is going to in-crease in future. This operation consumes nearly 0.5 million metric ton explosives consisting of 80-85 percent bulk explosives and remaining 15 to 20 percent non-permitted large diameter explosives. Quali-ties of bulk explosives play an important role in rock blasting. Post blast results like poor fragmentation, tight mucking, toe problems, improper muck profile and lower productivity of mine may require chang-es in explosive loading factor (amount of explosive used per unit of rock blasted ). The explosive load-ing factor is an extremely important index to assess the economy of blasting operation.

Jan 1, 2014