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By John Tatom, Michelle Crull, Robert Conway

The US Department of Defense Explosives Safety Board is sponsoring the development of a risk-based explosives safety siting program, SAFER. The fragment and debris hazard generated at the potential explosion site (PES) is critical at an exposed site (ES) over a significant range of standoff distances. The Science Panel Impact Debris Evaluation and Review (SPIDER) test program has been planned to develop improved predictions for the hazards inside an ES by fragments and debris. Data will include the mass and velocity required for perforation of the test cross-section and the characteristics of all debris produced inside the ES.

Jan 1, 2010

By Rolf Schillinger

Transport of Small Quantities of Explosives Material on Public Roads The transport of dangerous goods on public roads is extensively regulated by EU and national law. The transport of explosive material is not only done by forwarders but also by small companies and private persons with the goal of their own use. The following article tries to explain what is allowed and what is not.

Jan 1, 2010

By Dan McCutchen, Oettmeier

Kelly bar drilling and blasting is unique to Florida, the' Bahamas and other marine limestone areas in the world where blast holes are required but will not remain open for the loading of explosives. This type of rock formation usually yields 1.5 tons of recoverable rock compared to 2.2 tons per cubic yard for competent limestone. The loss of .7 tons per cubic yard is due to voids and sand in the formation. These deposits all contain water to the top of the blast holes which are collared only a few ft. above the ground water level. The working pit is a water filled lake which is excavated from the bank by draglines. These drills have been used in Florida for many years to depths of 65 ft or less.

Jan 1, 1991

By D Vrkljan, Z Ester

Excavating the building pit for the World Trade Center at Rijeka, it was necessary to blast over 160000 m3 of hard mass in fused condition. The building pit is located at a densely populated residential part of the main Croatian port Rijeka, close to the railway-track and traffic routes of the town. The permanent seismic monitoring points are foreseen on endangered housing and infrastructure facilities around the pit during designing and excavation of it. The seismic monitoring has been performed on 15 permanent points by occasion of over a hundred production and continuous blasting operations. The article considers the speeds of ground oscillations depending on applied maximum quantities of explosive charge according to fire degree, total quantities of explosives at the mine-field, structure of explosive charge, applied delay of mine boring and lines initiation mode and rock mass structure

Jan 1, 1999

By Elliott Giles

"Measuring a blast’s performance based on the bucket fill time or “diggability” has always been achallenge due to the subjectivity generally involved. The diggability of a blast is often based onopinions and speculation without the data to properly support the claim. This paper focuses howthe blast design can impact diggability and how it can be properly measured."

Jan 1, 2016

By John W. Kopp, David E. Siskind

Over 4 billion pounds of commercial explosives are used by the U.S. mining industry every year with an excellent and improving safety record. However, accidents involving explosives are seldom minor. They produce a disproportionate amount of fatalities compared to other mining activities, as reflected in the relatively high severity rates. The U.S. Bureau of Mines (USBM) has been analyzing blasting accident data obtained from the Mine Safety and Health Administration (MSHA) to determine the most frequent causes of mine blasting accidents, examining trends in these accidents, and identifying areas of needed research. This paper is an update of three previous blasting accident studies conducted on 4-year intervals by the USBM and published in 1983, 1987, and 1991, and is based on a total of 869 blasting accidents.

Jan 1, 1995

By John W. Kopp

The U. S. Bureau of Mines investigated flyrock and burden movement from blasting at several limestone and basalt quarries in the upper midwest. Blasts have been studied at 14 different sites using high-speed cinematography. Blasting was accomplished in 75- and 150-mmdiameter holes using a variety of explosives. Films from each blast were analyzed to show burden velocities, observed flyrock distance, and direction of throw in relation to the shot layout. This technique, in some cases, allowed determining point of origin and cause of the flyrock as well as the flyrock range.

Jan 1, 1994

By Braden Schmidt

The following full paper will go into the products, techniques and people who work in the avalanche control industry giving insight to the other members of the ISEE an overview of the niche blasting that is Avalanche Control.

Feb 1, 2020

By Gloria Contreras

The study aims to optimize the density of holes per tunnel section. The energy distribution, the one with the highest density, is used in the center of the diagram and is distributed homogeneously towards the contours with the lowest energies up to the contours to produce a perimeter control.

Feb 1, 2020

By Paul Worsey, Ron Ecklecamp, Scott G. Giltner, Ronnie Inman, Terry Drechsler

A blast monitoring program conducted at Chemical Lie Company’s new lime calcining facility near Ste. Genevieve, Missouri is discussed. The purpose was to develop blasting criteria for the construction and operation of the lime plant within the quarry operated by Tower Rock Stone. Further, it was imperative to accommodate production requirements into the blasting criteria. The major concern was the effect of blasting on the curing of green concrete during the construction of the storage silos and kiln stacks. In addition to discussing the susceptibility of curing concrete to blast vibrations, the paper also details how this varies with time.

Jan 1, 1996

By Anthony Konya, Calvin J. Konya

The publication, RI8507, from the U.S. Bureau of Mines established an envelope equation that related scaled-distance to peak particle velocity in an attempt to predict ground vibration in the design phase of a blast. This has been further modified by Oriard, Dupont, Konya & Konya, and others to develop more refined prediction models for specific situations to obtain better predictions. While these equations can be an ideal starting point for a greenfield blasting project or a project with no given information, these equations can have errors.

Jan 1, 2018

By Paul Klaric, Nicholas Bodley

Every blasting engineer or professional can attest to the age-old conundrum of obtaining accurate hole information on a large scale prior to loading explosive charges in a blast hole. Even though the benefits of QA/QC are well known and documented and are becoming increasingly important when digitizing and automating mining operations, the QA/QC process itself has not changed significantly over generations. The current methods where operators deploy measuring tapes of variable standards recording their subjective assessment of hole length on a paper blast map or manually transcribing to a tablet, are unreliable and non-auditable. Additionally, the process in its current form is time intensive, obtaining only moderate results and benefits, making it difficult or impossible to resource in today’s tight labour markets. Often only two data points, depth, and water presence, are captured when visiting the hole resulting in a high cost per bit of data. For these reasons, the process is seldom done on a large scale, let alone integrated. The QA/QC process in its current shape is a gap that will need to be addressed if autonomous blasting and mining is to become a reality.

Feb 6, 2023

By Ray Jambakhsh, John Okell, Frank Cook

"In early 1988, an experimental study was carried out at the Inco's McCreedy West Mine inLevack, Ontario. The objective was to develop blasting techniques which would allow themine to maintain production targets and reduce blast induced vibrations and overpressure.Due to its close proximity to the town of Levack (approximately 900 feet), particularconcern was expressed as to the vibration and overpressure resulting from the undergroundblasting operations."

Jan 1, 1993

By Huang Daguang, Paulo Couceiro, Juan Navarro

Mining is typically conducted through a set of interdependent unit-operations, which commonly include drilling, blasting, digging and hauling, in order to deliver the required ore material into the comminution circuit and to remove waste rock with minimum impact in the operation. In such complex environment, the identification of critical paths, and respective interfaces between different unit-operations, are necessary to determine a sustainable long-term operational program. Facing this challenge, adaptive cost optimization strategies are required to increase productivity and revenue while minimizing potential environmental impacts. Since the overall mining efficiency can be strongly impacted by blasting outcomes, an operating method based on the searching of the ideal blast design is required in order to minimize the mine total cost of ownership. The implementation of a consistent continuous improvement program requires specific care in terms of design, control and execution of the different stages of blasting. For that, the application of the most advanced technologies for rock characterization, based on drill monitoring systems, and smart explosive products, allows the improvement and control of blast results by adapting the explosive energy distribution to the rock condition, so as to optimize the performance of downstream stages such as digging, hauling and comminution. This paper describes the application of a heuristic optimization approach, where blast parameters are used as decision variables to evaluate the potential impact of several blasting scenarios on subsequent unit operations, under the continuous ability of modelling, measuring and calibrating operational performances along of the mine cycle.

Feb 6, 2023

By Hae-Moon Choi, Sang-Don Lee, Hee Soon Shin, Choon Sunwo, Chang-Ha Ryu, Hyun-Koo Lee

Building tunnels means dealing with what rock is encountered. Relocation of the site of the underground structure is rarely possible. Tunneling engineers and miners have to cope with the quality of the rock mass as it is. Different tunneling philosophies and different rock classification methods have been developed in various countries. Most of the rock classification methods are based on the response of the rock mass to the excavation. Tunnel support requirements could be assessed analytically, supplemented by rock mass classification predictions, and verified by measurements during construction. Rock mass classifications on their own should only be used for preliminary, planning purposes and not for final tunnel support. Design of blast pattern in tunneling projects in Korea is also for the most part prepared according to the general rock classification methods such as RMR or Q. It, however, does not take into account the blast performance, and as a consequence, produce poor blasting results. In this paper, the methods of general rock classification and blast design for tunnel excavation in Korea are reviewed, and efforts to develop a new classification method, reflecting the blasting performance, are presented. Copyright ©

Jan 1, 2004

By Thierry Bernhard, Johan Finsteen, Charles Dowding, Mathias Jern

To bring some clarity to how different standards relate to each other a project was initiated within the European Federation of Explosives Engineers (EFEE). The first part of the project was a literature study and a survey including an evaluation of the answers provided by members of EFEE. The results were presented at the International Society of Explosives Engineers (ISEE) conference in Denver 2020 as well as the EFEE conference in Helsinki in 2019.

Feb 1, 2020

By O Omidi

Selection of delay times to optimize fragmentation has been a controversial topic among researchers and blasting practitioners. This paper reviews previous experimental information and presents the results of new tests conducted in small blocks constructed using a commercial grout. The effect of the delay on the average fragment size, coarse fragmentation and uniformity of fragmentation is discussed. Fragmentation was coarser at extremely short or extremely long delays, while a fairly constant average size was obtained at a variety of intermediate delays. Uniformity, defined as the slope of the fragmentation distribution through the average fragment size, was poor at short and very long delays and relatively constant at the intermediate delays. Some tests attempted to minimize the effect of gas penetration by lining the boreholes with copper tubes. When this was the case average fragmentation changed marginally, while uniformity was significantly affected by delay and was typically smaller than in the unlined tests.

Jan 1, 2014

By M. Ganster

Austria’s biggest supplier of oil and gas, transports gas through the West Austria Gasline for domestic consumption. In addition, the OMV also works as gas carrier and ensures the transit into neighbouring countries.

Jan 1, 2010

By J. Rafael Otaíza, Francisco Mardones

This work has addressed the problem of creating a predictive model of the maximum particle velocities in the rock mass (PPV). The model designed specifically can model the subsequent vibrations of blasting based on geometric parameters, explosive loading, and the blasting process itself. Models based on artificial intelligence (AI) algorithms can find useful non-linear patterns to solve classification, regression, clustering, among other problems. They are flexible mathematical transformations adaptable to various objectives and types of data. With their different levels of abstraction, they can find a function that relates the input variables to the sought-after response. These models have been successfully used in similar contexts (Prashanth, (2018)) and have achieved state-of-the-art results in the field (Lawal, (2021)). The main challenge is to adapt them to the context of Chilean mines, in addition to including the geometric information of the blasting and the heuristic to obtain the set of optimal parameters, it is proposed to follow the work of (Simonyan, (2013)) and obtain "saliency maps" adapting it to tabular variables. We implemented an Artificial Neural Network (ANN) with a large number of neurons in the hidden layers. Models based on neural networks can find useful non-linear patterns to solve classification, regression, clustering, among other problems. They are flexible mathematical transformations adaptable to various objectives and types of data. With their different levels of abstraction, they can find a function that relates the input variables to the sought-after response. The literature shows that, for the problem of rock type identification, basic neural networks perform well (Simonyan, (2013)), but lack uncertainty estimates. This is a data-driven model, and in this sense, the model training was carried out using data from multiple operations in the large copper mining industry in Chile. In these databases, data consistency and the balance of the various independent variables that have the greatest impact on the model were ensured. With the above, the optimal hyperparameters of the model were determined, obtaining a predictive R-squared of 0.94.

Jan 21, 2025

By Clara Godoy, Paulo Couceiro, Juan Navarro

The continuous automatization and digitalization of the different stages involved in any underground construction bring new possibilities to optimize the operation. One of the most important requirements for the development of these projects consist of a proper rock mass characterization for optimizing the stages of the drilling, blasting and support cycle. In the last few years the road to digitalization has gone through data science and big data, showing the importance of data gathered to describe the geological and geotechnical environment that surrounds the operations. Since rock characteristics have an important influence in the drilling response, the technological advances in the sensorization of drilling machinery such as the Measurement While Drilling system (MWD) allow to gather the necessary amount of information to be applied in data science processes to evaluate changes in the rock mass with higher resolution than conventional methods. In this paper, Machine Learning techniques have been used to combine data monitored from the drill rigwith scanner profiles of the excavated sections to develop an automatic geotechnical rock mass characterization model able to estimate potential zones of over- or under-break of the remaining rock mass in underground blasting. By comparison of scanner profiles of the excavated sections with the blasthole positions, an Excavated Mean Distance (EMD) between the contour blastholes and the excavated profile has been obtained, which may be considered as damage measure. Considering blasting factors as constant, the model combines the rotary, percussive, hydraulic flushing and the rate of advance of the drilling, and the confinement of the rock mass by depth, to detect zones with different rock properties. This provide an early information of the rock mass condition around the blastholes and the prediction of expected overbreak generated after blasting, being possible to design more efficient bastings, in which each borehole is filled with the right and necessary explosive charge. The analysis comprises data from 57 blasts (around 1700 contour blastholes) and more than 4000 excavated sections.