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By Dale Ross, Bill Clements, Jim Spanos

Current world conditions are forcing the search for "green" energy technology in every aspect of our daily lives. Finding alternatives to petroleum fuels seems to be at the top of the list. The search for the "perfect" alternative is something like the never ending quest of the perpetual motion machine. Unfortunately, the laws of physics prevent us from getting something for nothing, and Murphy's Law normally gives us nothing for a lot of something. Regardless of Murphy, the quest goes on, and in our industry cheaper ANFO seems to be the popular subject.

Jan 1, 2012

By B. K. Rath

The Industrialization of a country depends on its mining activities to a great extent. In mineral production, India has a top rank not only in South Asia, at the global level too. Quantum of mineral production is almost directly proportional to the quantum of explosive production. Mining sector consume more than 80% of country’s explosive production. Due to rapid growth of mining activities in the country, the explosives industry has been developing very fast in terms of quantity, quality and types. , In this paper, India’s post independent chronological date regarding use of explosives, their types, their constraints and a profile of well-known manufacturers has been meticulously presented. A production figure for three years with system analysis has been presented. The paper also deals with present consumption pattern while making a futuristic forecast. In view of the anticipated changes that are to take place in mining industries in near future, the manufacturers of explosives have to pay a vital role. The paper highlights some concrete and valuable suggestions and recommendations. Small scale Companies have to limit their production to Slurry and Emulsion types of Cartridged explosives whereas the large manufacturing units have to concentrate on Bulk explosives, specialized explosives and better initiating systems. The large manufacturing units have also to make all concerted efforts to compete with global market for significant export. The Country for its rapid growth needs basic raw materials like Coal, Iron Ore and Limestone. So, the extraction of these minerals is of prime importance. The more we produce and consume, the more will be Industrialization. The Industrial growth rate has been around 6% during the last few years. As the Industrial growth rate is moderate, there is moderate increase in mineral extraction in the Country. Additional mineral extraction demands additional explosive production (Annexure-1).

Jan 1, 2000

By Uli Leiste

Two papers are presented which examine Air Deck Blasting, one from a computational aspect and the other from a shock aspect.

Jan 1, 2016

By Sérgio Augusto Ferreira, Alan Gerson Diaz Butron, Carlos E. Arroyo, Marcus Neves, Jorhs Enrique Casimiro Huayhua, Dieggo Santos, Eventomar Junior

The presence of natural underground cavities is normally a characteristic of iron ore deposits, specifically in tropical deposits. Brazil and the United States are the only countries that have a legislation to protect these structures, but in Brazil this legislation is very specific for the existing cavities in the federal territory. These cavities are classified by their level of relevance as high, medium, and low. From this perspective, its preservation becomes mandatory, especially, for those of high relevance in order to protect the species (flora and fauna) that live in them. When these structures are within the production phases, it becomes a challenge to exploit these reserves with the use of commercial explosives, since these structures condition and may restrict the use and amount of explosive charge. This paper presents the methodology of controlled blasting associated with predictability via realistic simulation in production polygons, applied in a Brazilian iron ore mine where there is a presence of high relevance natural cavities with restrictions in relation to the limits of Peak Particle Velocity (PPV), which is product of detonation.

Feb 6, 2023

By Rolf R. Schillinger

Subject of the paper are blasting vibrations as sources of environmental molestations including acceptance level,complaint level and damage level as well. Besides, the subject shows a comparison of international regulations and their problematical aspects. In consideration of blast induced immissions the subject shows that human annoyance has become an important place in blasting works. It provides a solution proposal how to minimize environmental effects of blasting works.

Jan 1, 1996

By Viktor Aranovich, Thomas E. Brown

The Almalyk Integrated Mining and Metallurgical Plant is located near Tashkant in Uzbekistan and is one of the former Soviet Union's largest copper producers. Almalyk consumes about 10,000 metric tonnes of explosives annually and expects this requirement to double by the end of the century as they implement a program to boost mine output.

Jan 1, 1998

By Alexandra Yuyali

The objective of this research work is to increase the drilling ratio represented in tons per drilled meter (ton/m) to reduce mining costs. One of the key characteristics of this research is the use of the ITH (in-the-hole) drilling rig with a water-powered hammer, also known as Wassara™. The patented Wassara™ in-the-hole hammer is powered by high-pressure water instead of air. To reach the objective, a new design of the blast pattern was implemented considering the following: Burden from 1.7 m (5.6 ft) to 2.8 m (9.2 ft) Spacing from 1.7 m (5.6 ft) to 2.7 m (8.9 ft) Drill diameter from 89 mm (3.5”) to 102 mm (4”) Drilling length from 15 m (49 ft) to 30 m (98 ft) Borehole deviation < 2% The result of this new design is the optimization of the drilling ratio (ton/m); having as a baseline 5.2 ton/m with traditional equipment and obtaining 13.7 ton/m with the ITH drilling, which generates annual savings of $2.43M.

Jan 21, 2025

By Rajesh Sonkar, Sanjeev Kumar

The deployment of Dragline machines in opencast coal projects involves huge capital expenditure as well as operating costs. The mine operators always endeavor to ensure smooth excavation of material by the Dragline machines while meeting the major objectives of safety, minimal disturbance to environment and optimal operating costs. Optimization of fragmentation through well designed blasts is fundamental in meeting part of the objectives is good fragmentation of rock or mineral proposed to be lifted by the Dragline machine. If the overburden lying over mineral is not properly fragmented, it may result in formation of ‘Toe’ the removal of which is the most arduous task in opencast coal mines. The mine operators always endeavor to achieve best possible results in blasting to ensure smooth operation of the high cost Dragline Machine. However, despite continuous efforts by the blasting engineers involved in bench blasting for the machine, the formation of ‘Toe’ is an ever nagging problem faced in large opencast coal projects eventually reducing the overall operational efficiency of mining.

Jan 1, 2011

By Lynn Long

We have seen many new developments in the explosive and blasting accessory category, but one of the most useful items is the blast control plug. Blast control plugs are cone shaped units that are placed in the stemming just above the explosive load. They are placed about 8 to 12 inches up into the stemming material.

Jan 1, 1996

By Rakesh Raghavaraju, Bibhu Mohanty

Prediction of fracture and fragmentation characteristics of a rock mass subjected to dynamic loads, such as in blasting remains a major technical challenge. The present study is aimed at characterizing the shock transmission properties in controlled experiments in small scale in a well-characterized granitic rock, under varying borehole coupling conditions. Single blast-hole tests were conducted in a granitic rock sample of 145 mm (5.7 inches) diameter and height. The boreholes (in two diameters: 6.4 mm (1/4 inch) or 9.5 mm (3/8 inch)) were loaded with detonating cord of varying charge weight (5.3 g/m or 25 grains/ft to 31.8 g/m or 150 grains/ft of PETN). The effect of explosion gas penetration into the target rock was eliminated by inserting a thin-walled copper liner along the borehole wall. Embedded carbon composite resisters were employed at varying distances from the borehole to measure transmitted shock pressure for two coupling conditions (i.e. air and water) at distances of 1x to 9x the borehole diameter. The paper analyzes the decay of shock pressure as a function of distance from the borehole, and its implication on shock-induced fracture properties of the target rock as the first step in predicting fracture and fragmentation behaviour in a well-characterized rock.

By Rakesh Raghavaraju, Bibhu Mohanty

The paper analyzes the decay of shock pressure as a function of distance from the borehole, and its implication on shock-induced fracture properties of the target rock as the first step in predicting fracture and fragmentation behaviour in a well-characterized rock.

Feb 1, 2020

By Thierry Bernard

Considering rock fragmentation by explosive as the ultimate goal in mines and quarries, vibrations are definitely one of the main drawbacks faced by the Industry. If we can accurately predict vibrations level and frequencies, taking into account the whole set of the involved parameters, this will bring a major benefit to each of us, in our daily production process optimization effort. The model presented in this paper answers to this need thanks to a "holistic" approach of the vibration mechanism. By holistic, we mean that we approach the vibration effect (wave propagation) as a whole, by understanding all of the mechanisms that contributes to the process and comprehending how they are connected.

Jan 1, 2009

By W. J. Birch, R. Farnfield

Nuisance caused by perceived high vibration levels as a result of blasting on quarries and opencast coal mine is now the number one environmental concern of residents living adjacent to such operations. The intrinsic nature of blast vibration monitoring and prediction is that it is impossible to accurately forecast the vibration levels that will be experienced by a given blast at a given location. Thus it is that a statistical approach to the problem is the only viable option. Unfortunately, persuading local residents living adjacent to a project that requires blasting that this is the best way of safe guarding both their homes and their quality of life is not an easy task. Thus routine monitoring involving both operators and regulators play a key role in building trust. However, public confidence is often shaken when regulators and operators use two different blast monitoring instruments side by side to record a blast at a local resident’s house and arrive at different results. To make certain that this does not happen in future, what is needed is a protocol that ensures that any two different blasting seismographs give the same peak particle velocity values at the same observation point. To do this all the equipment manufacturers, regulators and relevant professional explosive engineering bodies need to be involved.

Jan 1, 2014

By S K. Mandal, S Dasgupta

"Damage is classifi ed as loss in the integrity or deterioration in the quality of rock massand is infl uenced by methodology of excavation on the geo-technical properties of rockmass. Overbreak, on the other hand, is the result of damage and is quantifi ed in either of the terms viz., extra mucking, shot-creting, application of extra support system and extension of scheduled completion time. Damage or overbreak in rock mass by the impact of blasting, is generally unavoidable but, the magnitude can be minimized so that it does not deteriorate the quality or integrity of structure. The paper, here, analyses magnitude of overbreak of a powerhouse cavern with respect to different blast patterns implemented at the site. The magnitude of overbreak was analyzed in terms of profi le measurement with the help of laser profi ler and percentage of halfcast markings observed on the periphery rock wall. The paper revealed the impact of decoupling ratio, blast pattern and geometry of blasting patch on the magnitude of overbreak. The authors observed that presence of un-favourable joint pattern or foliation plane along the periphery rock wall couldn’t contain magnitude of overbreak within allowable limit. The analyses revealed that percentage of half-cast markings on periphery rock wall was infl uenced by response of rock towards detonation of explosive and cannot be a single parameter to assess the effectiveness of a blast. The analyses also revealed that magnitude of overbreak for down-stream wall was more than that observed in up-stream wall."

Jan 1, 2008

By Italo Onederra, Miguel Araos

"In order to characterize non-ideal explosives, the explosives industry rely on unconfined velocity ofdetonation tests and where possible underwater pond tests. The information obtained from such tests isquite helpful, however it cannot tell us much about the dynamics of the detonation reaction process. The detonation process has been studied for ideal explosives and the reaction zone length have been measured. However, for non-ideal explosives, that type of information is not available. Therefore, the primary aim of this work was to capture the detonation process of a non-ideal explosive using high speed video camera to determine the zone length."

Jan 1, 2017

By Park Yun-Seok, Jung Seung-Won, Hwang Nam-Sun, Song Jin-hyuk, Kim Young-ho

This study proposes a new blasting vibration estimation formula that reflects the vibration reduction characteristics of electronic detonators, which are not considered in the current MOLIT blasting vibration estimation formula. Test blasts were conducted across six types of Korean open-pit blasting designs. The results of the test blasts showed that the K value for electronic detonators decreased by approximately 30% compared to electric detonators. Predicted Peak Particle Velocity (PPV) analysis indicated a reduction effect ranging from 30% to 31% across various types. By incorporating this reduction in the K value into the MOLIT blasting vibration estimation formula (K=200), a new electronic detonator blasting vibration estimation formula (K=140) was proposed. Using this new formula, the blasting damage range (R) was calculated under various vibration limits to evaluate constructability improvement. On average, the R value for electronic detonators decreased by about 17%, with significant reductions of around 41% observed for TYPE I under certain vibration limits. In conclusion, the adoption of electronic detonators in open-pit blasting operations improves blasting efficiency, reduces economic costs, and significantly enhances constructability. Electronic detonators have demonstrated superior performance in minimizing damage to safety facilities compared to traditional electric detonators, thereby proving their practicality and effectiveness in blasting operations.

Jan 21, 2025

By Gungor Tuncer, Ali Kahriman

This paper presents the results of ground vibration measurements carried out in Hisarcik Boron open pit mine located on the west side of the central Anatolia near Kütahya province in Turkey. Within the scope of this study in order to predict peak particle velocity level for this site, ground vibration components were measured for 304 shots during bench blasting. In blasting operations; ANFO (blasting agent), gelatin dynamite (priming) and delay electric detonators (firing) were used as explosives. Parameters of scaled distance (charge quantity per delay and the distance between the source and the station) were recorded carefully and the ground vibration components were measured for all blast events using 2 different types vibration monitors (1 White Mini-Seis and 1 Instantel Minimate Plus Models). The absolute distances between shot points and monitor stations were determined using GPS. The equation of square root scaled distance extensively used in the literature was taken into consideration for the prediction of peak particle velocity.

Jan 1, 2006

By Angel Rafael Fernandez, Yahya Khader Al-Harbi, Benjamin Cebrian Romo, Antonio Morato Medina

The kingdom of Saudi Arabia has set the goal to diversify their economy from oil into different fields including mining. As the vast Arabian Peninsula is explored, orebodies of Aluminium, Copper, Gold and Phosphates are found in high grades and tonnages. Hard rock is present in most of the projects and require high quality blasting in regard to ore dilution, wall control and fragmentation. Maaden Gold has currently 4 open pit mining operations 1 new opening and 2 underground. More projects are coming online in the next few months and years. A new generation of mining engineers need to apply drilling and blasting techniques that compete with modern and efficient open pit and underground mines.

Feb 6, 2023

By Art Frye, Lee Pratt, Gaichang Zhao, Greg Newman

This paper will discuss the Wight Pit wall slash at the Mount Polley open-pit copper-gold mine that scavenged a high grade block of ore from two double-benches of the pit wall. The Wight Pit orebody, discovered in 2003, is located in the Northeast of the property with the southeast pit wall approximately 50m (165ft) from the edge of Polley Lake. In early 2009, the Wight Pit was nearing completion while an estimated 150,000 tonnes (165,000 tons) of ore averaging a grade of 1.4% copper remained just inside the southeast pit wall. The ore block started 24m (78ft) above the pit floor and extended up another 48m (157ft) with a 70o plane defining the back of the block.

Jan 1, 2011

By Mark S. Stagg, Rolfe E. Otterness, Stephen A. Rholl

The Bureau of Mines fired seven test blasts in a 22-ft bench of limestone, screening the material to investigate the influence of explosive type and between row delays on fragmentation. Four 4-hole, single-row test shots were conducted evaluating dynamite, ANFO, emulsion, and a 60-40 emulsion-ANFO mix. Three 12-hole shots, with three rows of 4-holes, evaluated delays between rows of 24, 36, and 120 ms. Accurate in-hole electronic delays were used, firing within 1.5-ms of the nominal delay. All seven shots had a 6- to 7-ft burden, 10-ft spacing, with a hole diameter of 3-1/2 in fired on a 12-ms delay between holes in the row. The tests were instrumented with strain gauges grouted in the burden region examining stress wave and gas pressure effects. Fiber optic probes were used to confirm timing and to obtain detonation velocities.

Jan 1, 1989