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By Mike Higgins

"The purpose of mining and its related industries is the removal of, and usually the subsequentprocessing of, material from the earth. This includes mining for minerals, quarrying for stone, and civilexcavations. Where this involves rock, the most common method is to fragment the rock by blasting. "

Jan 1, 1997

By Theirry Bernard

The era of non-electric systems as an initiating system has revolutionised the blasting world by introducing a very safe initiating system that is reliable, with initiation sequence possibilities that are superior to those of purely pyrotechnical or electric systems. Electronic initiation has brought with it accuracy, programming and controls that were lacking in the non-electric systems. However, it has also led to a certain degree of complexity, which works against user-friendliness, sometimes introducing a few constraints that are balancing out the intrinsic performance of electronic detonators. The introduction of a hybrid initiation system, Electronic and Non Electric, offers accuracy, and flexibility that were lacking in non-electric systems, whilst removing the inherent complexity of electronic systems. This paper endeavours to summarise the advantages and disadvantages of non-electric and electronic initiation systems that have been recorded after years of experience on site. The paper will then describe how a hybrid system only keeps the advantages whilst eradicating the disadvantages, via a case study.

Jan 1, 2007

By Virgil J. Stachura, Calvin L. Cumerlato

The Bureau of Mines conducted a series of tests to develop a blasting method that would reduce overbreak and rockfall hazards at a limestone quarry in northeastern Wisconsin. Reductions in overbreak were achieved by shortening the main explosive column and reducing the explosive load in shortened stemming zones in shotholes which were to form the highwalls. Two blasthole diameters, 3 and 4 inches, were used with 7 by 7 foot and 9 by 12 foot burdens and spacings respectively. ANFO, Comsol 300, or PowerAN were used in the body of the shots and Gelmax or 40 pct extra dynamite cartridges were used in the reduced load zones. Smoother highwalls were visually apparent, however further analysis by seismic refraction techniques were performed as an aid to studying overbreak within the rock mass.

Jan 1, 1989

By Wendell W. Harris, Stanley J. Vitton

In the United States each year it has been estimated that expansive soils cause approximately $9.0 billion in damage to buildings, roads, airports, and other facilities. This figure alone exceeds the damage estimate for earthquakes, floods, tornadoes, and hurricanes combined. Unfortunately, some cases of expansive soil damage (swelling) are blamed on rock blasting operations if the blasting operations are located within the immediate area. While simple tests, such as the Atterberg limits test, can characterize a soil as expansive, it does not necessarily answer the question whether the foundation soils are causing distresses to a structure. In particular, it appears that once a soil has been labeled as nonexpansive it is no longer considered as a problem soil, in which case blast vibrations become the prime suspect.

Jan 1, 1996

By Hapsari Rosa, Ross Cowie

Conventional blasting activities in the mining process use various types of explosives, with the primary raw materials being Ammonium Nitrate and diesel fuel. The quality and specifications of the two raw materials significantly affect the performance of explosives. One program from the Indonesian Ministry of Energy and Mineral Resources requires mixing 30% Bio Diesel 30 with 70% diesel fuel oil in several industrial sectors, including mining, to reduce greenhouse gas emissions and stabilize CPO prices. This program aims very well for environmental sustainability and the palm oil business. However, it turns out that this change impacts the performance and results of the blasting process in the mining industry, which is the appearance of fumes. This paper will discuss the tests carried out in the laboratory on Bio Diesel 30, the explosive products used, and rock samples were taken from a mine in East Java, Indonesia. The aim is to determine what factors can cause fumes utilizing a mixture of Bio Diesel 30 with pure diesel fuel. The parameters tested were visual differences, infrared spectrometry, density and viscosity, surface tension and contact angle for Bio Diesel 30, stability test for explosives, and the SEM-EDS method for rock samples.

Feb 6, 2023

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.

By Clara Godoy, J. A. Sanchidrian

In this paper, Machine Learning techniques have been used to combine data monitored from the drill rig with 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.

Feb 1, 2020

By Brian Hawkins, David Bradley, Rachel Gooding, Lucas Rodriguez, Patrick Wilson, Kevin Wegman, Dhruv Mittal

The Department of Homeland Security (DHS) has undertaken a probabilistic risk assessment (PRA) approach to quantifying the infrequent, yet high-impact explosive terrorist attacks on the United States (US) homeland and aiding in mitigating that risk through efforts ranging from intelligence gathering, defense postures, detection architectures, partnering with industry to prevent acquisition, and informed medical response. Based on an evaluation of existing model options, a path to the realization of an exterior explosive model (EEM) that builds upon existing models while meeting runtime requirements, maintains consistency with existing DHS chemical, biological, radiological, and nuclear (CBRN) consequence models, and provides sound estimates of the human health consequences of explosive terrorism attacks in open-air urban and rural environments.

Jan 1, 2018

By Carlos Campos Junior, Leonardo Soares Chaves, Raul Carretero Hoz, Renato Jacome Costa, Davi Bastos Martins de Oliveira

The Vale’s Serra Sul mine, also known as S11D project, is one of the world’s largest open pit iron ore mines, located in Brazil’s Amazon region. The mine produces around 90 Mt of high-quality iron ore annually. Its unique orebody enabled the S11D project to adopt a truckless mining system with In-Pit Crushing and Conveying (IPCCs) for ore exploitation and waste stripping. The IPCCs system requires crushing the waste, mainly composed by the jaspilite lithology, and is also conveyed to waste deposits several kilometers away from the mine. Due to Amazon’s environmental restrictions, the project was designed with preliminary geological knowledge, leading to the installation of primary crushers not designed for the hardest jaspilite, with uniaxial compressive strength (UCS) up to 500 MPa. This resulted in low waste crushing performance, affecting stripping ratio and threatening future production. A project was developed to improve the fragmentation of the jaspilite, allowing higher waste IPCC production, and reducing the risk to the production due to low performance of waste crushing and conveying. The first challenge was the independence of the geological and the geomechanical models, while only the geological model was considered in blast designs, the geomechanical model describes six waste groups of jaspilite classified according to their strength. A new geological model was then created to incorporate the geomechanical classification, allowing different blasting design according to the rock strength of the jaspilite. The blasting pattern on most compact jaspilite was reduced 27%, from 22m² to 16m² in 9 7/8” diameter holes, with a proposed theoretical reduction of 23% of the P80, from 326mm to 250mm. The second challenge was the implementation of the new design, as this pattern size and the high powder factor (2.9 kg/m3) were paradigms for such a large iron ore mine. The measured results have shown 25% reduction of the P80, the crushing rate was increased by 17% (230t/h), saving around $2.4 million annually in crushing and conveying system maintenance.

Jan 21, 2025

By Brent Coleman, Wade Hutchison

The Montgomery Bell Academy project is a parking garage structure topped by a soccer field. This project included expanding parking and moving the present tennis courts. The project is located adjacent to an affluent historic neighborhood that posed some special public relations challenges.

Jan 1, 2012

By Mohammed Alkazimi, Katie Grantham

The purpose of this paper is to quantify the risk to both the environment and surrounding infrastructure from a pipe sealing implosion. Both accuracy and the precision in determining how a submerged infrastructure damaged by underwater explosions performs provide better decision-making capabilities for managers facing impending oil spills. This determination is vital, especially for both emergency and crisis management teams, as categorized consequences based on both the nature of the structural layout and the surrounding marine environment assist in identifying whether or not the utilization of this technique is applicable. Thus, the decision maker’s aim, in a crisis, is to minimize any associated risk that might result in aggravating the situation by endangering both the infrastructure and marine life. Therefore, the resulting risk matrices will enable technical personnel who are not experts in explosive technologies to be armed with the information necessary to determine if this mitigation technique is applicable to their situation.

Jan 1, 2013

By Carlos Enrique Arroyo Ortiz, Jadir Pedro Alves

This paper presents some of the results obtained during the research work about the use of technologies and digital transformation in the process of rock drilling in open pit mines. The use of automation presents itself as a disruptive factor and a driver of improvements that provide sustainability in rock drilling. Seven main operational parameters were utilized to combine measurement while the drilling (MWD) with other information generated by the equipment during hole drilling, in six different lithologies in an iron mine, located in the central region of Minas Gerais in Brazil. Adjustments and corrections were made to the data collected in order to minimize external influences other than the rock itself, to ensure the effectiveness of the analyses. Finally, we sought to compare the performance of the drilling process in manual and automatic operation modes. Thus, making it possible to show the efficiency and impact on the sustainability of rock drilling operations in open pit mines.

Feb 6, 2023

By Jair Koppe

The unsatisfactory blasting effect is mainly related to the improper selection of design parameters of drilling and blasting scheme. In order to evaluate the rationality of drilling and blasting scheme, scientifically, this paper brings forward a method for scientific evaluation of blasting scheme. This method evaluates the blasting scheme by observing the accuracy of drilling, explosive density, charge, lumpiness analysis, filling length, slope surface design, floor level, vibration monitoring and flyrock. The evaluation involves different stages of blasting construction and implementation, such as terrain survey, drilling, charging, environmental impact and safety evaluation. Through this method, several key problems for improving blasting scheme design can be determined by analyzing each parameter. This method improves the key parameters of blasting design by analyzing blasting results and establishes the relationship between blasting effect and technical design.

Feb 6, 2023

By Ruilin Yang

The vector sum peak particle velocity (PPV) of blast vibrations describes the blast vibration intensity more completely than the PPV of a single component waveform. It is more logical to use a vector sum PPV as a vibration limit than using a single component PPV. In 1980 the USBM recommended the frequency related peak particle velocity criterion. So far this method has been only applied to single component waveforms, but not to the vector sum PPV since there is no method available to associate a frequency to the vector sum PPV. The present paper describes a method to define a principal frequency associated with vector sum PPV. The method is based on the weighted average of the principal (zero-crossing) frequencies of the three tri-axial components at the time of the PPV.

Jan 1, 2015

By Dr. Anthony J. Konya

The modern era has seen a boom in virtual training platforms. This study details the effectiveness & applicability of online training in comparison to in-person training for the drill & blast industry.

Feb 1, 2020

By Hans-Peter Rossmanith

Fracture mechanics (Atkinson 1987, Broek 1988, Rossmanith 1978-2002, 1983, 1997, Kanninen & Popelar 1985) and wave propagation (Graf 1975, Rinehart 1975) form the main ingredients in the new electronic detonator based blasting technology. The full potential of using short delay initiation timing in bench and underground blasting can only be exploited if the underlying physical processes are properly understood. From a structural geology point of view, in many open pit mine operations, blasting is performed in incompetent and/or loose rock. Under such conditions the stress waves produced by blasting very quickly dissipate in the rock mass and often their energy cannot effectively be put to work. This contribution shows the effect of open and closed joints – and to some degree also faulting – on the blast wave field and shows the influence of structural geology on the blasting result. A simple engineering method which combines wave propagation and impact mechanics is developed in order to assist the non-scientifically trained blaster in understanding blasting in blocky rock formations. Extensive use will be made of the so-called Lagrange diagram which was introduced in detail in the author’s previous lecture at ISEE 2003 (Rossmanith 2003). This presentation can be considered a continuation of the 2003 presentation.

Jan 1, 2004

By Denard A. II Brandt

Today I would like to share with you some blasting practices used in the thick coal seam mines of Northeastern Wyoming. I will begin by giving you a general overview of a thick seam coal operation at The Carter Mining Company's Rawhide Mine. I will then discuss the blasting procedures used at this operation. The Rawhide Mine is one of 13 mines operating in the Eastern Powder River Basin of Northeastern Wyoming. Approximately 23 billion tons of recoverable coal lies in the Powder River Basin. The Rawhide Mine is currently producing approximately 8 million tons per year. Rawhide is the 9th largest coal mine in the United States according to 1982 production. We also received the 1982 Sentinels of Safety Award for being the safest surface coal mine in the United States. Rawhide's permitted capacity is 24 million tons.

Jan 1, 1984

By Denise Clarke

Homeland Security Qualifications (HSQ) personnel were instrumental in developing the UK’s suite of Explosive Substances and Articles (ESA) National Occupational Standards (NOS) (also known as "competences") on behalf of the Standards Setting Body for Explosives, Munitions and Search Occupations (SSB for EMSO).

Jan 1, 2013

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 Alvin D. Christmas

The missing link is a connector between the congested downtown area of Knoxville, Tennessee adjacent to the former World's Fair site, the I_40 I_75, and Western Avenue traffic arteries. This connecter was designed to accommodate the 37,470 motorists who presently travel through these highly congested narrow paths to be replaced by the 21.8 million dollar Henely Street Connecter. All construction and blasting was to take place while existing traffic was re_routed so as to allow access between the downtown area and the vital interstate corridor. To avoid major traffic problems, the project was to be accomplished in three phases: (1) the Western Avenue viaduct demolition; (2) two new viaducts to be constructed; (3) the open box cut at Henely Street next to the L & N Depot. Due to the past attempts by the Fort Sanders Community Home Owners group and the Historical Society to stop the Henely Street Connector, this project involved a very comprehensive blasting damage control program with special provisions of .5 inches per second measured at the foundation of the closest structure.

Jan 1, 1995