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By Radhe Krishna, Mutale William Chanda, Timothy Mwale

Blasting as a process is the emplacement of industrial explosives into blast holes suitably located to a free surface and detonated. Every blast hole containing a certain amount of explosive charge undergoes impulsive loading when detonated and results in the dynamic transfer of a powerful shock wave to the surrounding rock. It is the shock wave that brings about rock breakage when the tensile stress produced upon reflecting from the change in material density or free face overcomes that of rock material tensile strength. However, this shock wave comes along with unwanted destructive consequences such as damage to remaining rock, ground vibration, noise and fly rock. The above mentioned consequences pose a great threat to the Community of Wusakile, Kitwe as Mopani Copper Mines Plc wishes to increase its production by expanding the pit towards the community that lies within 150 m (164 yd) from the pit rim. As a requirement from the Zambia Environmental Management Agency (ZEMA), all blasting operations close to the community must maintain at least below the maximum vibration threshold of 10 mm/s (0.3937 in/s) PPV-Peak Particle Velocity or else risk closure of the mine (AMC,2009). In order to satisfy the above statement, a good understanding of explosives is required. This paper therefore presents the phenomenology of rock breakage by explosives with much emphasis on electronic blasting and how best this process can be controlled in densely populated communities. Factors affecting maximum projection distance such as, size of the fragment, shape of the fragment, angle of projection, the state of confinement of an explosive charge, were also studied. In addition, design faults, deviation in implementation and unforeseen geological conditions were also considered. The paper discusses the above facts based on research.

Jan 1, 2015

By Robert Hopler

On June 13, 1912, the final decree of dissolution of the DuPont explosives trust was handed down, and the resulting new companies began operating at the beginning of the new year. The property assets granted to (or retained by) the companies were as follows:

Jan 1, 2014

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 C. Kosloski, E. McCullough, A. Fox, S. Reed

This paper serves as a reference guide for creating or strengthening student chapters of the International Society of Explosives Engineers. This includes chapters that are just starting, currently undergoing transition in leadership, or that are in the process of rebuilding. ISEE student chapters have great potential to increase student involvement and national membership, and can benefit from formalized strategies to help them do so. Several key strategies are introduced and should be employed to promote organizational participation throughout the university system.

Jan 1, 2016

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 Shulin Nie, Mats Olsson

The mechanism of rock fracture by explosive is a fundamental in rock blasting. It is generally believed that the shock waves from the detonation initiate the fractures. Then the detonation gases penetrate into the fractures and elongate them. However, our previous researches indicated that the detonation gases do not contribute significantly to the fracture propagation. In our latest experiment, blasts have been carried out in 8 large granite blocks. The main goal was to study the fracture mechanism, namely to determine whether the shock waves or the detonation gases fracture the rock.

Jan 1, 2001

By Ignacio Humeres Valdivia, Alejandro Ferrada Vergara

In the latest years, the use of innovative blasting techniques has become more frequent in mines all over the world. Such techniques allow the miner to be more aggressive in the distribution of explosive energy into the rock mass, e.g., stretching blasting patterns to improve fragmentation. Considering the different rock mass conditions and more energetic blasting designs, misfired shot events have occurred. After cause investigation, initiators have shown evidences of deformation by impact and/or loaded boreholes have resulted in emulsion desensitization, both presumably affected by dynamic pressure.

Jan 1, 2015

By Sandy Tavelli, Thomas L. Barkley

This discussion will present a case study in developing solutions to a metropolitan quarry’s public relations, legal, environmental, and productivity problems. It details an extensive and detailed project to address the blasting practice in a medium sized quarry that is surrounded by residential and industrial zones. The principle work was done over a four-month duration during the normal production season. It included detailed drilling and blasting audits for baseline information. In addition, geologic characterization, seismic modeling, correction of deviations from best practices, and implementation and monitoring of precise electronic timing to provide dramatic solutions for the quarry. The quarry is in the near suburbs of a large metropolitan city. It is framed on two sides by residential municipalities and on two sides by industrial zones. At the start of the project, the quarry was in court as a result of the lawsuit by one of the neighboring towns that was suing to close the quarry. The lawsuit had progressed to the advanced stage where in the Judge had appointed an arbitrator to make the decision of continued operation. This arbitrator was to observe our progress and recommend to the Judge the disposition of the case.

Jan 1, 2004

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 Gungor Tuncer, Ali Kahriman, Abdulkadir Karadogan, Savas Gorgun

The principal disturbances created by blasting in open pit mines are vibrations, air blast and fly rock. All of them, under some circumstances, caused damage to structures nearby and apart from this can be the source of permanent conflict with the inhabitations who live close to the operation. Therefore, prediction of ground vibration components is of great importance for the minimisation of the environmental complaints. This paper presents the result of ground vibration measurements induced by bench blasting realised at Can Open Pit Coal Mine located close to the residential area of Can town. Within the scope of this study, in order to predict peak particle velocity and determine the slope of the attenuation curve for this site, ground vibration components were measured for blast events during bench blast optimisation studies over a long period. During the study, while the parameters of scaled distance were recorded carefully, the ground vibration components were measured by means of two different types vibration monitors (White Mini-Seis and Instantel Minimate Plus Model) for 54 blast events. At the end of evaluation an empirical relationship with reasonable correlation was established between peak particle velocity and scaled distance for this site.

Jan 1, 2001

By Alastair Torrance

The performance of commercial explosives is clearly influenced by the conditions under which they are used. Mining companies are supplied with Technical Data Sheets which provide details about explosive properties and its suitable application. These are generally produced using laboratory techniques which may not accurately reflect the quality and performance of the product in the field.

Jan 1, 2013

By Ron Woolf, Corry Goumans

This paper describes rock slope remediation performed along America’s first Superhighway, the Pennsylvania Turnpike and in particular, the specialized drilling equipment designed and built by Pacific Blasting to complete this work. This S-month project was performed on an existing rock cut slope within the Bedford Narrows, a gap formed by the Juniata River through Evitts Mountain. These rocks are in the folded Juniata and Tuscarora Formations within the Valley and Ridge Province and strike northeast with near vertical to slightly overturned bedding.

Jan 1, 2001

By Shazad Hosein, Bill Birch, Catherine Johnson, Toby White, Liam Bermingham

Air overpressure (AOP) from blasting can give rise to a significant number of blasting complaints from residents living adjacent to blasting operations from mines, quarries or civil engineering projects. High amplitudes of AOP are usually associated with the lateral movement of a vertical free face, but it can also be caused by the upward lifting and the venting of gases through the surface of the blast area.

Jan 1, 2018

By Tony Rorke, Sydney Thabethe

A large overburden blast was carried out at Douglas Colliery, Middelburg Mine Services, close to a national road in South Africa. The road is a busy route between Witbank and Bethal and damage to the road could not be risked. The section of road next to the blast was particularly prone to damage, because it had been mined out on its eastern flank, and the large blast was to take place on its western flank. There were thus three potential damage risks: 1. Fly rock damage to the road surface 2. Vibration damage to the road substrate 3. Damage caused by bulk displacement of the block supporting the road into the void on the mined out side. This paper presents the design and blasting methods used to control the blast and avoid these three risks. Electronic delay detonators were used in multi-decked holes. Signature data were used to determine the blast timing to make sure that delays were used that would provide destructive interference. The timing direction and sequence was decided using wave interference patterns to direct repeated shocks away from the road. The precise detonators and the odelling capability allowed effective control of the blast vibration result. Each hole was charged with two explosive decks separated by a deck of aggregate to limit the charge mass fired per delay and thus limit the reaction forces acting towards the unsupported road. The vibration and blast results are presented in the paper, together with the design that was applied. Details are provided on how the blast was charged and primed. The detonators that were used are described and the timing design is presented.Copyright © 2004 International Society of Explosives Engineers 2004G Volume 1 - Blasting Next to an Unsupported Road Using Electronic Detonators 1 of 13 It is concluded that damage risk to nearby structures can be effectively controlled using electronic delay detonators, provided the appropriate modelling is applied to obtain the most effective delay periods.

Jan 1, 2004

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 Sushil Bhandari, Amit Bhandari

In this paper, a case study is presented of a large global cement company using a cloud and mobile based platform across 17 of their mines consistently over a large number of users over a period of over two years. The use of a blast platform is detailed which include blast designs, blast data collection and the trends in terms of results.

Feb 1, 2020

By Aiden Carey, Jim Kennedy

During December 2007, Lake Cowal Gold Mine located in New South Wales, Australia experienced a significant pit wall failure. The wall failure resulted in the deposition of a large quantity of saprolite consisting largely of clays and lake bed sediments to the bottom of the Phase 1 open pit mine. This wall failure ultimately buried two loaded blast patterns.

Jan 1, 2011

By Ajoy Singh

A study was conducted to investigate the damage potential to underground multi-seam openings caused due to vibration generated by open-pit coal mine blasting. The objective was to recommend optimal explosives weight per delay to be detonated in open-pit blasts to ensure the safety and stability of underground openings. Sixteen blasts with varying charge weights and initiation sequences were conducted at Samleshawari open-pit mine and eighty four blast vibration data were recorded in the Hingir Rampur underground colliery in India. Analysis of vibration data showed that roof of the underground openings vibrated with higher amplitude of vibration compared to pillars and floors. The amplifications of vibration in the roof at the junction were upto 4.3 times the pillar vibration. It was observed that coal chips detached from roof when the peak particle velocity reached 131 mm/s or high. The vibration magnitude recorded was higher in upper seams openings than in below seam openings. Rapid attenuation of vibration was recorded in below-seam openings at similar locations. Appropriate particle-charge weight-distance equations were established to calculate the safe explosive weight per delay to be detonated in open-pit mine for safety of multi-seams workings of underground mine. The support for the galleries and junctions were further modified for the working seams to ensure greater safety.erground Coal Mine

Jan 1, 2012

By Rob Grant, Manuel Lopez Cano, Mike Briggs, Ken Fletcher

The scorched desert sands and life giving waters of the River Nile in Egypt have been the back drop to awe inspiring engineering feats for over 4,700 years. The latest engineering marvel to grace the land of the Pharaohs is the Mubarak Pumping Station Project at Toshka. This ambitious project aims to open up an area of 607,000 hectares (1.5 million acres) of barren desert to irrigation based farming with the supply of 29 million tonnes (32 million tons) of water per day, drawn from Lake Nasser on the river Nile. It is anticipated that this currently unpopulated area of southern Egypt will soon flourish and become home to several million Egyptians who will conduct their lives around the water supplied by the 230 kilometers (144 miles) of concrete canals. An integral part of the pumping station is the intake canal. The canal was excavated in two sections – the dry excavation, and the wet excavation. The wet excavation comprised of some 5.5 million cubic meters (7.2 million cubic yards) of rock to be drilled, blasted, and excavated, from the surface of the lake. The challenge at hand was how to achieve this safely, quickly, and cost effectively, with water depths of up to 45 meters (148 feet), excavation depths of up to 47 meters (154 feet), blast production rate peaks of up to 30,000 bank cubic meters (39,200 bank cubic yards) per day, blistering summer air temperatures up to 60°C (140°F), and security concerns about the storage of large quantities of explosives in the Middle East region. The solutions to these challenges were engineered by UEE Explosives and centered around the use of a microgel bulk explosive called Rioflex™ and an international team of engineers and operators from three continents. The microgel and accompanying pumping system allowed pumping rates of up to 17,400 kg (38,400 lb) per day, and more importantly, enabled the bulk product to remain as an oxidizing matrix whilst in transport and storage, transforming into an explosive only moments before being pumped into the blastholes. This case study outlines the underwater drill and blast process employed at the Mubarak Pumping Station Project at Toshka, and the novel solutions to the unique challenges encountered.

Jan 1, 2004

By John Arrell, James Stuart

We have developed a tester that is uniquely able to measure the no-fire power level of certain types of electro explosive devices (EEDs). In the past, it has been difficult to establish a no-fire power level for nonlinear conductors, such as semiconductor-bridge (SCB) EEDs, and conductive-mix EEDs.

Jan 1, 2011