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By Douglas Rudenko PG, Jay Elkin, Siavash Mahvelati Ph. D.

Very little studies have investigated the behavior of cracks in unlined tunnels over long periods of time, especially when such flaws are subjected to blast-induced vibrations. Using a pool of 30+ blast events, a positive correlation was found between the peak particle velocity and peak crack movement.

Feb 1, 2020

By Claudio Lechuga, Carlos Scherpenisse, Juan Rafael Otaiza

From the analysis of drilling process, Block Model information, drilling pattern data and expected fragmentation targets; GBlast® software optimizes the explosive charge design in order to standardize the particle size of each blast.

Feb 1, 2020

By E. Vilaescusa, J. Eloranta

The work presented in this paper investigates the influence of non-ideal detonation characteristics related to the blasthole diameter, base emulsion sensitivity (micro-balloon sensitised versus unsensitised) and percent emulsion on the explosive shock energy available to break rock using ANFOemulsion blends. A series of theoretical equal powder factor bench blasting patterns with hole diameters of 127mm (5”), 140mm (5.5”), 152mm (6”) and 165mm (6.5”) are compared to assess the non-ideal confined shock-state work energies. The Non-Ideal Shock Energy Factor (NSEF), which is the available shock energy per cubic meter of blasted material (MJ/m3) or kilocalories per cubic yard (kcal/yd3), is used to compare the different blasting patterns charged with a range of ANFO-emulsion blends from zero to 50% emulsion.

Jan 1, 2012

By Robert Hopler

HUDSON MAXIM A Noted Inventor of High Explosives ALTHOUGH the subject of the present sketch has been a tireless worker in many fields of activity, his name is best known in connection with his work in the development of high explosives and their application to modern ordnance

Jan 1, 2012

By Ayman Tawadrous, Hendrik Botha, Simon St J Tose

The early miners and their mules always had the challenge of transporting unstable dynamite underground. The modern pumpable explosives, whilst far safer, still present a major logistics challenge for the mobile charging units (MCU). The challenge today is the efficient explosive delivery into declines, ramps, and vertical shafts, often requiring the MCUs to travel excess distances up and down to surface to re-load. Alternatively, the management of cassettes or ISO containers is utilized to deliver the pumpable base emulsion to the MCUs at the working face. Additionally, local laws and regulations regarding shaft clearance further compound the task and result in pausing other operations in the shaft or decline or ramp until the completion of the explosive transport. This paper examines the research & development challenges of dropping base emulsion down a vertical pipe to depths in excess of 1000 m (3280 ft.), either to an underground storage or directly into the MCU, depending on the depth. The boreholes (with pipes) are drilled in close proximity to the underground work areas. The paper also discusses the rheology of the emulsion within these vertical pipes as well as the economic benefits of such an innovative system. The learnings gained from this work, along with examples demonstrating the significant reduction in MCU travel and the safety benefits, are presented for the industry to consider moving forward.

Jan 21, 2025

By Sven-Erik Johansson, Gosta Rundqvist, Donald Jonson

In Stockholm a new road traffic system called Södra Länken (Southern Link) will be in operation in late 2004. The total length of the road system is 6 kilometres of which 4,5 kilometres run through tunnels under suburbs immediately south of Stockholm inner City. The new traffic tunnels together with existing Metro tunnels, which mostly are in rock, will be the determining factor for blast design for many projects in the future. To set reasonable and safe permitted vibration levels the Swedish National Road Administration, Stockholm Region and Stockholm Transport Rail System have together financed a project to determine guide levels for blast-induced vibrations in traffic tunnels in rock. The purpose of the project has been to establish guide levels that are appropriate for different types of rock tunnels.

Jan 1, 2004

By W. Fourney

In the late 70’s and early 80’s in conjunction with other oil and gas well stimulation studies, personnel from the Dynamic Effects Lab performed model testing to demonstrate the effectiveness of utilizing an open section of borehole just before a plug. We called the process stem induced fracturing. The open section beneath the stem was used to increase the pressure magnitude and spread out the duration of the pressure pulse. This technique was later utilized to by Frank Chiapetta (1) in the fracture and fragmentation of rock in quarry blasting situations. He called his technique air deck blasting. In fact, Frank found that the Russians had previously discovered the same technique. There is currently interest in utilizing air deck blasting with an open section of hole beneath the explosive at the bottom of the bore hole to better remove the toe in a fragmentation shot. This paper reviews the development of stem induced fracturing and then describes a series of model tests conducted to measure borehole pressure at points along a borehole when an explosive charge is detonated at the midpoint of the borehole. Tests were conducted in both stiff boreholes (aluminum) and less rigid boreholes (PMMA-Plexiglas). Pressure time profiles were measured at the charge site, midway between the charge and the bottom of the hole, at the stemming at the top of the borehole, and at the bottom of the borehole. Crack initiation sites and crack propagation were also determined in the PMMA models. Some high speed pictures were taken of the event in the PMMA.

Jan 1, 2006

By Ricardo Dr. Chavez, Mathieu Lachamp, Rob Dr. Farnfield

Pueblo Viejo is an open pit gold mine in the Dominican Republic which is always looking forward to implement the newest technology in the industry to improve all processes. Focusing on one of the pillars of the department and our company, digitalization, we’ve been looking for the technologies that allow us the automation of data generation, supervision and process innovation. That’s where a new Drill and Blast software takes place, helping to integrate the process from the beginning to end, right after the pattern is designed until it’s blasted, allowing us to track results like vibration, fragmentation, performance, cost and inventory of each blast in a single platform. The software helps engineers to generate back analysis by blast, bench, pit, month and many other ways, in a timely friendly manner. Therefore, we can catch business opportunities and improvement for the drilling and blasting process.

Jan 1, 2019

By Debra Satkowiak, Ronald Thomas

The Institute of Makers of Explosives (IME), a non-profit safety and security organization founded in 1913, is known for its industry best practices, Safety Library Publications (SLP), some of which have been incorporated into rules by regulatory agencies. The IME developed the first commercial storage, quantity distance (Q/D) table titled “The American Table of Distances” (ATD). It was developed by IME’s legacy association in 1910 and was originally based on observations of structural damage from 117 accidental explosions involving small to very large amounts of explosives, primarily dynamite and black powder. In 1930, the IME published a book, compiled by Ralph Assheton, called the “History of Explosions on Which the American Table of Distances was Based”. The distance in feet in the ATD were founded on the measurements at which inhabited buildings sustained substantial structural damage from the accidental detonation of explosives. For example, minor damage such as window glass breakage and the “shaking down” of plaster was not considered substantial structural damage. Other damage to property that was readily repairable was also not considered “substantial.” It was concluded that unless some integral portion of the building was damaged, the occupants would not be subjected to serious risks.

Jan 1, 2017

By Steve Dillingham

A blast site incident has just occurred. Tensions are high, and, as the blaster, you’re in charge of the crisis at hand. Your mind is reeling, your thoughts frantic. The main areas of concern for you at the scene are to deal with immediate problems...aid the injured, take a head count, assess the damage, call emergency response, contact company headquarters, calm the neighbors, update your customer, and respond to the press on site. You feel as if all the bases have been covered...but, then again, have they? One of the biggest mistakes blasters and their companies can make is not including their Insurance carrier in the critical on-site accident procedures and emergency call list. Unfortunately, many companies believe that they are immune to the perils that can often, within a matter of minutes, create chaos that only happens to someone else.

Jan 1, 2002

By Chanhwi Shin, Hyeongmin Kang

Mine optimization is a key strategy in the mining industry that focuses on improving the efficiency, productivity, and sustainability of mining operations. To achieve mine optimization, digitalization is essential for modernizing mining operations and attaining optimal performance. Due to the importance of mine digitalization, various software and platforms have been released to support this effort. Furthermore, by integrating these advanced technologies, mines can enhance processes, leading to significant economic and operational benefits. However, integrating data from various sources and collaborating across different platforms remains a significant challenge in the mining industry. Generally, data for mine optimization, such as mapping, smart drilling, FMS (Fleet Management Systems), fragmentation analysis, or vibration analysis, are collected and analyzed separately on different platforms. This separation makes it difficult to aggregate and utilize data comprehensively for overall mining process optimization. During the digitalization process, obstacles arise due to these complexity, variability, and sharing issues of data across different maker, sources, and methods. These challenges highlight the need for seamless integration to achieve optimal mining operations. Thus, this study applied a total solution that can cover the entire Drilling and Blasting (D&B) processes. The blast design was performed using actual terrain mapping data, and drilling and charging were conducted following a guide based on the blast design plan. After blasting, loading and hauling distances and fuel consumption were measured, and fragmentation for each blast was evaluated. All measurement tasks were automated to minimize human error. By collecting all data in one server, it became possible to perform an overall evaluation for each blast, allowing the identification of optimal values. In conclusion, to evaluate the optimization effects for each mining process, one month of integrated data collected on a single server was used. Compared to the period before the Total solution was implemented, there were notable improvements: a 25% enhancement in hole spacing, a 60% improvement in floor flatness, a 23% reduction in average fragment size, and a 19% improvement in fragment uniformity. Regarding cost savings per blasting volume, the improvements were 11.7% in drilling, 9.3% in explosives, 7.6% in loading, and 17.5% in hauling.

Jan 21, 2025

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 Paul Worsey, Gillian Worsey

The explosives industry is about to reach a critical turning point in human resources. The average age of employees of the largest US explosives company is over 50 and an estimated 5,000 engineers are due to retire from the mining industry over the next decade, with less than 200 mining graduates per year nationally. Not just in the USA, this is a worldwide problem. In Canada the Mining Industry Human Resources Council (MIHRC), reported that older mining engineers are retiring early – at the age of 59.5 on average. It predicts that mining companies will need to hire 370 mining engineers by 2016 and 665 by 2021. The Minerals Council of Australia has predicted the need for an additional 86,000 mining professionals and skilled mine workers by 2020, and the Indian mining industry is also facing a shortage of between 2,500 to 3,000 engineers per year.

Jan 1, 2014

By Benjamin Cebrian

Rock blasting at quarries represents multiple challenges not easy to see at first sight. Aggregate industries face similar or superior prices for explosives while extracting a material that usually is of less value of metal mining operations. Therefore, learning to optimize a quarry operation can be a perfect training for a position in blasting at larger metal mining operations.

Jan 1, 2010

By Lindsay Wade, Peter Dare-Bryan

Benches in surface mines often contain known areas of ore and known areas of waste, which must be mined selectively. When rock is blasted it not only fragments but is also physically, and non-uniformly, moved. Risks therefore exist of ore being lost if treated as waste and of mill feed being diluted by waste. Both possibilities carry serious fmancial implications.

Jan 1, 2001

By Orica Peru, Pedro Lozada

Maintaining a continuous mining process during thunderstorms is one of the primary challenges in Peru's open-pit mines. Safety protocols necessitate the establishment of exclusion zones to minimize the risks of unplanned detonations. During such conditions, loading and hauling equipment must be relocated or, in the worst case, halted, directly affecting productivity (t/h). Implementing a wireless initiation system mitigates the risk of unplanned detonations during electrical storms by eliminating the use of electrical cables that are susceptible to electrical discharge. This study documents the implementation of this system in a copper mine located over 3,500 meters above sea level in Peru, where electrical storms between December and March necessitate modifications to blasting schedules and limit the number of drills fired per event. Through a test using wireless detonators, a key performance indicator (KPI) was established to ensure safe and continuous operation during thunderstorms. The results were significant: 20 blasts were successfully executed, firing approximately 5,000 holes and moving around 10 million tons of material, all without safety incidents or critical operational deviations, achieving zero misfires and no scheduled blast suspensions. Shovels SH001 (ore) and SH002 (waste) continued to operate together for an additional 100 hours continuously during thunderstorms, generating a potential saving of USD 3.3 million by continuously sending ore to the plant during the testing period under stormy conditions. Additionally, the blasting initiation time was reduced by 25%, eliminating two activities that involved the use of surface connection cables. This reduction led to over 150 hours of decreased personnel exposure to interactions with vehicles and environmental hazards such as dust and noise. Furthermore, the number of holes fired in a single event increased by 50%, enhancing the blast tonnage capacity and reducing equipment stops due to evacuation and reentry from two to one.

Jan 21, 2025

By Mark Bosse

This is a paper demonstrating the use of a fixed wire and trolley system to deliver 2 or 5 lb cast primers (with 2 meter cap/fuse assemblies) deep into avalanche terrain. This avalanche terrain is mitigated using explosives prior to being opened to guests.

Feb 1, 2020

By Gordon C. Petersen, Gary A. Almeraris

This paper describes the controlled blasting techniques required to mine a rock tunnel section of a main interceptor located in the Boston Metropolitan area. The 3m (10 ft) x 2.8m (9.25 ft) horseshoe shaped tunnel was driven 490m (1600 ft) by conventional drill and blast methods. The geology varied round by round and consisted of five highly faulted and jointed igneous rock types. The tunnel intersected numerous slickenslides and open mud seams which hampered both drilling and loading operations. Smooth blasting wee critical in order to keep overbreak tc a minimum in this extremely hard but blocky ground.

Jan 1, 1991

By THOMAS BAMFORD, Dale S. Preece, Amir Behbahanian, Mick Lownds

An important aspect of blasting is rock movement and final muck configuration. Computer modeling of this process has been done in 2D for many years, revealing insights into the blasting process and enabling some design optimization. Since blasting is inherently a 3D process, 2D modeling misses the 3D aspects of blasting results and can lead to inaccurate conclusions. Software development environments in many fields are evolving in 3D, enabled by steadily increasing computer speed, memory, and software efficiency. These same environments are also available for modeling of many physical processes, including rock blasting. This paper documents the development of 3D blast movement modeling techniques that utilize 3D computational mechanics and modern computing environments to predict explosive induced movement of hundreds of thousands of distinct cubic elements representing the rock mass. Blast induced ore travel and final location can now be predicted with reasonable accuracy and acceptable run times. The importance of Energy Partitioning was documented and demonstrated by GEM-2D (Geologic Element Motion) at the ISEE conference in 2024. This software is titled GEM-3D and includes this Energy Partitioning capability. This paper documents a GEM-3D example of ore movement during rock blasting and demonstrates ore dilution as well as the final location of different rock types as influenced by the blast.

Jan 26, 2026

By Langdon T. Mitchell, Karl Ingmarsson

The title is not referring to jewelry; nor is it about diamond core drilling. This article is instead about an emerging application for diamonds, hard rock percussive drilling with diamond drill bits. Diamond’s outstanding wear resistance has long been taken advantage of in core drilling. However, until now diamond has been less successful in hard rock production drilling in the mining and quarry industry.

Jan 1, 1999