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By Ph. D. Favreau, Favreau Patrice B. Eng, R. F.

Geology is important in mining by helping to identify the rocks which contain sufficient valuable ore to justify their excavation. Geologists give a geological name to each rock type, so geology is a player in blasting; when a blaster has successfully blasted rock of a given geological name at a former site, and he later has to blast rock at another site whose rock has the same geological name, then his first trial often is the same method as he used at the former site, since the geological name of the rock is the same

Jan 1, 2019

By Andreas Gaich

A new 3D fragmentation analysis method for muck piles is presented. It works with aerial imagery from UAVs (drones) and handles entire muck piles with minimum user intervention.

Feb 1, 2020

By Alton Dunaway, Kevin Sullivan, Charles Gray, Doug Hall, Kevin Grant, Kelly Thiel, John Paulson, Bruce Leland, Cole Boyd

Beaver (Castor canadensis) are responsible for economic losses exceeding $4 billion over the last 4 decades in the southeastern United States alone. A large portion of these damages occurs to public roads and highways, forests, agricultural resources, and other property from flooding caused by beaver dams. The United States Department of agriculture, Animal Plant Health Inspection Service, Wildlife Services (WS) program is a non-regulatory Federal program directed by Congress to assist resource owners with managing damage caused by wildlife.

Jan 1, 2007

By Adrian Moore, Dominic Hooton, Alan Richards

Significant factors affecting airblast overpressure (AOP) emissions include charge mass per delay, distance from the blast site, burden, stemming height, and delay timing, topographic shielding, and meteorology. The effect of charge mass on the frequency of the airblast produced, and the delay timing required to control the level of airblast overpressure is explained by two case history examples which were not affected by topographical shielding and meteorology. One is a cast blast with a charge mass per hole of 1000 kg (2200 lb), and the other is a quarry blast with a charge mass per hole of 64 kg (141 lb), These examples show that the delay interval necessary to prevent an increase in AOP levels must be increased with an increase in charge mass per hole. The effect of a ‘soft-start’ technique where a reduction in AOP levels is achieved by decking only the initial front-row holes is also illustrated.

Jan 21, 2025

By Travis A. Davidsavor, Charles Dowding, David A. Provost, Yonggang Gou

This paper compares measured blast induced strains on operating, full scale, buried pipelines with three similar past studies. The recently performed study represents realistic and modern pipeline blasting techniques combined with modern data acquisition. The evaluation compares measured PPV and strain, as well as calculated stress, at equivalent scaled distances.

Feb 1, 2020

By Gary Cavanough

The spontaneous exothermic reaction of ammonium nitrate explosives with sulphide-containing rocks, commonly referred to as reactive ground, is a site-specific condition that can lead to spontaneous detonations. Mine sites typically carry out regular assessment of ground for reactivity. In Australia, reactive ground testing is conducted according to the Australasian Explosives Industry Safety Group (AEISG) Code of Practice. This paper presents a new method to assess reactive ground. The new method can be completed on the mine site or in the laboratory. The new method allows samples to be tested in hours not weeks, as required when using the method prescribed in the AEISG Code of Practice. The new method also provides an explanation of why ground is reactive or not reactive, Whereas the AEISG Code of Practice provides a reactive, not reactive or marginal results with no understanding of reason for these results. Case studies on the use of weathering agents, pH, sulphide content and carbonate content will be reported. These case studies identify instances where the testing as per the AEISG Code of Practice provides false positive and false negative results. A false positive result will require the use of inhibited products when they are not actually required which increases costs and reduces productivity due to the need to used multiple explosive products. A false negative result increases the risk of an unplanned initiation of a blast hole.

Feb 6, 2023

By Alexander Hauck, Dimitri Jung, Uli Leiste

This paper describes results from small scale tests conducted to determine the distribution of impulse on target plates when subjected to loading due to the detonation of a buried mine. The tests were conducted with saturated sand, dry sand, and water as the loading media. Tests were conducted for flat plates and for plates with angled bottoms. Previous testing has shown that angled bottoms can reduce the total vertical impulse delivered to the vehicle significantly. Different stand off distances were investigated as well as loading of the targets both on center and off center. It is very important to know not only the total impulse delivered by a detonating charge but also how this impulse is distributed over the bottom of the vehicle. A complete understanding of specific impulse will permit those parts of the vehicle, taking the greatest amount of loading, to be sized properly. Experimental results were compared to analytical expressions provided by Westine and Tremblay.

Jan 1, 2010

By Regina Rocha, Miguel Humpire

One of the challenges within unitary mining operations is blasting, which has a significant downstream impact on the following processes, which is why mining companies ensure the results of the blasting process through joint work with explosives specialists’ companies.

Feb 6, 2023

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 Anderson Meireles, Leonardo Soares Chaves, Raul Carretero Hoz, Carlos Eduardo Soares Feliciano, Renato Jacome Costa

The large iron deposits in the northern region of Brazil located in the Amazon Craton have in common the presence of natural cavities. These cavities primarily occur in the upper layer of the ore body, formed above hematite mineralization. Their origin remains a topic of debate, often associated with hydrothermal drainage processes and erosive evolution. Over time, these cavities have become integral to the local environment, each contributing to the regional ecosystem of fauna, flora, and the significance of speleothems found within them. Managing these cavities poses a significant challenge for iron mines in the area. On one hand, they must preserve the cavities from anthropogenic actions, while simultaneously handling heavy equipment and large volumes. In 2023, the development of the mine took place towards the cavity under study, revealing systematic deviations in vibrations recorded during nearby detonations as the blasting got nearer. To address this, a work plan was put in place, emphasizing a straightforward approach: constructing lithology-specific vibration models, defining charge abacuses, and optimizing timing to reduce charge amplification. Implementing this methodology significantly improved adherence to the vibration limit, resulting in an around 50% reduction in standard error. This paper presents the consolidated work that allowed mining activities to continue in the area through controlled blasting, effectively mitigating potential anthropogenic damage in sensitive areas.

Jan 21, 2025

Currently there exist several explosive quantity-distance (Q-D) rules variously exercised by most countries to protect personnel and property against the effects of accidental explosions. These regulations apply to manufacture, transport and storage of explosive products. This paper reviews the technical basis behind these regulations, as they apply to commercial and military explosives. The characteristics of a blast wave and missiles issuing out of an explosion site and their role in determining the level of damage to a target are discussed. The need for further research on the effect of detonation of charges of non-standard geometry, and under confined conditions such as tunnels is discussed. The challenge in estimating the net quantity of explosives involved and calculation of its TNT-equivalency is also highlighted.

Jan 1, 2011

By David E. Siskind

In the early 1980's, the Bureau of Mines published four reports of structural response and damage from surface mine blasting, vibration monitoring, and analysis methods. These findings replaced simpler and less restrictive Bureau criteria dating back to 1962 for ground vibration and 1943 for airblast.

Jan 1, 1991

By E. Contestabile, B. von Rosen, P. Lightfoot

As part of an accident investigation ANFO was subjected to various abusive tests. A tractor-trailer carrying 18,000 kg of blasting explosives, caught fire, burned for approximately 30 minutes, and then detonated. A series of tests was designed to observe the behaviour of ANFO when subjected to different thermal stimulus tests and more specifically, the Height-to-Detonation Test. Three diameters of steel pipes were used in the Height-to-Detonation Tests thereby simulating cylindrical columns within a pile of ANFO. The ANFO samples were then subjected to various thermal stimuli to initiate a reaction. Through the use of some instrumentation, the response of large ANFO samples was recorded and its behaviour, including the occurrence of phase changes will be analysed.

Jan 1, 2001

By John Floyd, Larry Wardrip

A series of tests were conducted to evaluate the performance of a high density, high velocity cartridged explosive. The tests included two production blasts in a limestone quarry and two production blasts in a granite quarry. To quantify blast and product performance, each blast was monitored with the following equipment: l Two (16mm (Lo Cam) high speed cameras (500 images per second) l Velocity of detonation recorder (I million samples per second) l Four face motion accelerometers (1 million samples per second) l Digital seismograph The fragmentation distribution produced by each blast was quantified with digital image analysis The benefits of the use of high velocity, high density toe loading was quantified in terms of: l Vibration reduction l Fragmentation improvement l Excavator performance In addition to the field tests, a comprehensive evaluation was performed to determine the cost/benefit relationship of the use of the toe load. This paper will include the findings of the study along with guidelines for use in other quarry operations.

Jan 1, 2002

By Andreas Bienz

The safety of persons from accidental explosions and fires during manufacture, storage, transport etc. of explosives, pyrotechnics, propellants, firework and ammunition is most commonly assessed according to prescriptive rule-based approach: Safety is given when all requirements which are listed in numerous regulations and directives (such as e.g. safety distances, limited quantities, protective installations etc.) are complied with. Such a deterministic prescriptive rule-based approach is quite easy to apply but has got disadvantages, however: The actual state of safety in a specific case is not explicitly and quantitatively expressed, and it is not distinguished between the endangered individuals and the whole group. As a result, the effects of the safety measures cannot be measured. This is why uneconomical and in the worst case useless safety precautions cannot be avoided. In addition, waivers are difficult to negotiate, meaningful and sound arguments for pro and con being lacking.

Jan 1, 2007

By Hairong Zeng, Matthew Baumann, Shahram Tafazoli, Edmond Chow

Measurement of rock fragmentation has evolved from a completely subjective and manual process to a statistically objective and semi-automated process. However, ultimately, the vision is to achieve a statistically representative and fully-automated process. From the blast optimization perspective, it is critical to receive reliable rock fragmentation results quickly to incorporate into the planning of subsequent blasts. Since manual rock fragmentation measurement methods tend to be time consuming, a fully-automated method is the practical way to meet these requirements.

Jan 1, 2012

By Glenn Tobin

The overarching goal in modern drill and blasting operations is that of optimising mining operations to achieve higher levels of productivity, safety, profitability and sustainability. Air decking, a technique used in drill & blasting to optimise explosive product use while achieving a target rock fragmentation1, is a technique that when executed correctly is proven to achieve consistent results independent of rock strength and the position of the holes (single, multiple, vertical, slanted), as well as being proven to reduce super-fragmentation (under-size or fines) while able to achieve optimal fragmentation, especially in the stemming zone2. The ‘shock absorber effect’ if the air deck reduces ground vibration and air blast3. Additionally, the practice of loading explosive product directly in saturated ground without dewatering or lining prior is an increasing global trend.

Jan 1, 2012

By Andrew Moore

It has long been common practice to conduct drilling and blasting operations at surface quarries in the Midwest in close proximity to near-vertical highwalls. The main reasons for such an approach, and the limited use of adequate safety controls, can be associated with higher costs, operational constraints, lithological requirements, property boundary restrictions, inadequate quarry planning, or a lack of understanding of highwall risks. Working in proximity to highwalls, without effective controls, exposes personnel and equipment to increased risk of incidents. In recent history, there have been isolated incidents involving equipment damage, or personnel injury/fatality around the United States. However, the Midwest market has largely escaped the effects of such incidents, even though the exposure rate is high. Awareness about this matter greatly increased on January 19th, 2021, when a significant incident occurred at a quarry near Green Bay, Wisconsin. As a crew was loading a typical blast near a highwall, a ground fall occurred, and multiple rock fragments struck a laborer working on the bench below. This individual sustained significant and life-altering injuries.

Feb 6, 2023

By H. S. Venkatesh, G. Gopinath, R. Balachander, G. C. Naveen

Punatsangchu Hydroelectric Project Authority is constructing 1020 MW underground hydroelectric project in Bhutan. The project envisages construction of concrete dam, Desilting Chamber, Head Race Tunnel, Power House Complex and Tail Race Tunnel. Tunneling is one of the major activity in any underground projects as they are driven for multiple activities. By and large the tunnels are a major part of connecting networks from surface to caverns/underground working sites. Many tunnels in hydropower project are part of water conducting systems and one such important tunnel is the Tail Race Tunnel in this project and had to be excavated in thinly foliated rockmass conditions by D&B method.

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