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By Pierre DePasquale, Ricardo Chavez

Lowering of quarry energy consumption participates to answer both environmental and financial issues. The “EE-Quarry” European project, supported by the European Commission (EE stands for Energy Efficient), develops a new and highly effective modelling and monitoring Energy Management System technique to improve Energy Efficiency and move to a low CO2 emission rate in the nonmetallic mineral industry. Within this global quarry project, blast design, as the first link in the chain, has to be optimized in order to satisfy requirements of downstream operations. The authors have been developing and implementing an operational methodology using continuous field measurements and field adaptation methods for blast design. It drives the drilling and blasting work, aiming at a more energy efficient and environmentally friendly operation. Based upon actual local conditions (rock-mass assessment, face geometry, borehole deviations, etc.), blast patterns are optimized through a specific hole-by-hole blast design software. It provides a better and more consistent energy distribution, to achieve a better rock fragmentation, while avoiding explosive overconsumption. The software also calculates total energy inputs and the drilling and blasting contribution to Greenhouse Effect. Coupled with methodical fieldwork and variable density explosives, it has been leading to a real reduction in energy costs and greenhouse gas emissions. As the project is now reaching its final stage, demonstrations were conducted in various quarries around Europe. Several simulations were carried out and compared to the site data, in order to propose enhancements for the different phases (extraction, loading, hauling, crushing and transport) while bearing in mind the environmental impact of the quarry. This blasting methodology allows to assess the carbon footprint of drilling and blasting in conjunction with the downstream operations, thus to evaluate the global carbon footprint of quarrying. Copyright ©

Jan 1, 2015

By Fumihiko Sumiya, Koichi Kurokawa, Yukio Kato, Tetsuya Sawada

In some metal mines, it is a serious problem the decomposition of explosives which occurs suddenly by contact with ore containing pyrites under high temperature conditions. In the present paper, we investigated heat resistant properties of emulsion explosives and other industrial explosives by contact with ore containing pyrites under high temperature conditions.

Jan 1, 1992

By Dale S. Preece, Ruilin Yang

"Air-decks are often employed for presplitting along the final highwall of a blast and are sometimes also included at the bottom or in the middle of explosive columns in the production portion of a blast. Shock wave physics is an important part of air-deck behavior since the bulk explosives in the column impart a shock into the air-deck where the air shock then passes through the air-deck at a rapidlyattenuating velocity. Through both high-fidelity modeling and shock physics theory it is shown that theresulting pressure in the air-deck is two orders of magnitude less than the detonation pressure of theexplosive."

Jan 1, 2017

By Curtis Garner

Griesemer Stone located in Springfield, Missouri has supplied aggregate in Southwest Missouri since 1946. In 1954 the decision was made to mine the formation and utilize the mined out area for warehouse space. As advancement proceeded, entrances and small diameter air shafts for ventilation were needed and had to be added. It was decided in 1989 to sink an 8' diameter air shaft designed to move 200,000 cubic feet of air per minute with the help of (4) four 50,000 CFM Loren Cook Fans.

Jan 1, 1991

By Max Pena Woolcott, Winfried Rosenstock, Maria Chappuis, Walther Hennig

"In a Peruvian-German Technical Cooperation project for the Mining Sector the ""Milpo-cut"" along with the electric initiation system has been successfully implemented in a Peruvian metal-ore mine.Specific savings in drill work and explosives consumption up to 50 % have been achieved in headings and slopes. The positive results have motivated further Peruvian mining companies to introduce the new technique."

Jan 1, 1994

By Garfiansyah Rayes

In 2023, an Indonesian coal mine experienced significant contamination of an emulsion blend explosive by dynamic mud and water flow, triggered by flooding due to exceptionally high rainfall. This intrusion into explosive columns compromised the stability and efficiency of blasting operations, thereby impacting overall mining productivity. The extent and impact of these contaminants on the stability and performance of the emulsion blend explosive were rigorously analyzed through a robust assessment methodology that included comprehensive field measurements and controlled laboratory experiments designed to replicate the challenging site conditions. Utilizing a combination of theoretical calculations and Computational Fluid Dynamics (CFD) simulations, this study evaluates the kinetic interactions between dynamic mud flows and emulsion explosives within drill holes. The methodology integrates Torricelli’s theorem for velocity assessments and Darcy’s Law for understanding the penetration mechanics of mud into the emulsion blend. CFD simulations are further correlated with actual blast data to assess discrepancies between theoretical predictions and real-world outcomes. Results demonstrate a significant reduction in the velocity of detonation (VOD) of the explo-sives, traced directly to mud contamination levels, which align with the quantified penetration rates in the study. Practical measures for mitigating such contamination are proposed, including the reinforcement of water-ways, culverts, and bund walls at drilling locations based on validated simulation data. Additionally, rec-ommendations for operational adjustments during high rainfall events are discussed, aiming to enhance blasting safety and efficiency. The paper concludes by suggesting future research directions towards the development of more resilient emulsion formulations and enhanced predictive modeling techniques to better forecast the impacts of en-vironmental variables on explosive performance in mining operations

Jan 21, 2025

By W. J. Birch

The dedicated documenting of blast design and vibration monitoring results forms part of the best practice methodology for today’s blasting operators. This allows regression curves to be constantly updated and in turn compatible charge weight determinations are based upon the most current data. The point can arise however when so much data becomes agglomerated that variations in blast design, geology or monitoring location response and their effects can pass unobserved and start to have an adverse effect on the forecasting capability of the regression due to a deterioration of the standard error statistic. The simple solution would be to only compile like-for-like blasting returns, but this prospect can quickly become unworkable due to the number of potential variables. In addition it is very difficult to spot subtle variations by simply examining a standard scaled-distance curve mainly due to the intrinsic data scatter that is always present together with the logarithmic nature of the regression curve. If indeed a variation is thought to be apparent, how can the degree and magnitude of its influence to be quantified? The Likelihood Ratio Test when applied to regression data can diagnose subtle variations between data sub-sets and provides a comparative statistic as to the degree of variation. By analysing datasets in such a way, levels of compatibility are obtained, indicating which sets can be combined in order to increase prediction capability.

Jan 1, 2004

By Jeffrey E. Loney, Andrew F. McKnown

Recovery of contaminated groundwater migrating through bedrock can be very difficult due to the low transmissivity of many bedrock fracture systems. To overcome these difficulties, a system of controlled "trench" blasting has been used on several projects to assist in cutting off and collecting groundwater plumes in bedrock. By using a combination of trench blasting and presplitting techniques, linear "fracture" zones are created in appropriate locations to significantly increase flow into recovery wells and control plume migration.

Jan 1, 1995

By Alejandro Ferrada Vergara, María Jesús Barros Godoy

Reducing costs while maintaining productivity and achieving good results is a constant challenge in mining operations, especially in the drilling and blasting stage, since a bad blast can affect production plans, increase costs, affect safety and jeopardizing the pit stability. Examples of undesirable blasting effects are: flyrocks, boulders, loading equipment damages, lower production rates, etc. In some of the biggest open pit mines using conventional blasting patterns visited by the authors, the pattern does not adjust properly to the rock mass, in most cases blasting polygons are large and the rock mass condition is variable within the designed blasting pattern. On the other hand, conventional blasting patterns with stemming columns use 40-50% of the blast hole with inert material (the stemming). Moreover, blasting engineers spend efforts to improve fragmentation results by increasing explosive charge in spite of having the negative effect of ground vibrations, with little or no success. The classic approach is "the more explosive in, the better the fragmentation is", furthermore it is assumed this relation is direct and infinite, but it is definitely wrong. This work challenges the notion of a limitless direct relationship between explosive charge and fragmentation, this means this is partially true but just up to a certain limit. In other words, there is still room to improve energy distribution among the classical blasting techniques without increasing the explosive energy by using air decks. In the work to be presented air decks are built using conical shaped stemming plugs called Paraplug®. The results obtained suggests a wedge effect acts in the bottom of the stemming column that cushions the shock wave and the air deck to reduce the detonation pressure (this is due to the decoupling factor resulted from the air deck). The demonstration shows improvements in fragmentation results, reduced vibration records accompanied with lower dust column and costs savings in explosive charge.

Jan 21, 2025

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 Jose Pineda, Abraham Lindo

The Panama Metro System’s Network expansion involves excavating a launching shaft for a tunnel boring machine (TBM) to traverse beneath the Panama Canal. The blasting needed for this shaft construction poses significant challenges due to the presence of concrete walls encircling the excavation. These walls must remain intact throughout construction and the tunnel's future operation. This case study is focused on devising and implementing safe blasting techniques crucial for the shaft's construction, ensuring the preservation of surrounding concrete walls and project equipment. As the interest was potential damage to the concrete walls, an appropriate vibration threshold for this project was also required as an alternative to the traditional U.S. Bureau of Mining RI-8507 limit (USBM RI8507). Blast modeling software was employed to conduct a series of blasting simulations. Parameters like hole diameter, spacing, depth, explosive type, and initiation methods were varied to evaluate their potential effects on wall stability and damage risk. The simulations revealed that smaller diameter holes and reduced spacing between blast holes would effectively mitigate the risk of wall instability. Additionally, utilizing electronic delay detonators and carefully planning the blast hole detonation sequence proved critical in minimizing potential damage. Executing these blasts in the field presented unique challenges, including strict charge per delay thresholds and logistical constraints. Consequently, continuous adjustments to blasting parameters were made and comparative result analysis. Beyond providing a safe blasting strategy for the TBM launching shaft, this study offers invaluable insights into adapting blasting designs to align with environmental and structural safety standards. These findings hold great potential to shape guidelines for analogous sensitive construction projects. They underscore the importance of leveraging prior research as a reference point, engaging with project designers and local authorities, and continually conducting testing and adjustments to ensure project success.

Jan 21, 2025

By Timothy Smith, Matthew Ryan, Dr. Anthony Konya

Hybrid specifications are a relatively new style of specifications specifically for the drilling and blasting industry that has seen widespread use over the last decade with the U.S. Army Corp of Engineers. This paper analyzed how this methodology was applied to develop this specification for the Soo Lock Deepening Project.

Feb 1, 2020

By S. Klerkx, R Battulwar, J Valencia, J Sattarvand, E Emami, M. Soleymani Shishvan

A new technology for energy distribution optimization, supported by NIOSH.

Feb 1, 2020

By Robert Jacob Cefalo

In 2019, the Bingham Canyon Mine, owned by Rio Tinto Kennecott Utah Copper Company, mined through the active underground that dewaters the pit. The active underground required the limitation of vibrations to avoid catastrophic damage or damage that would require work to the shotcrete and additional roof support. The surface design of the current sector was mined next to and through portions of the active underground.

Feb 1, 2020

By B Mohanty

The current basis for rating of commercial explosives is examined, with particular emphasis on calculated bulk and weight strengths, detonation velocity and underwater energy measurement. The calculated strengths still form the basis for selecting explosives for most blasting applications, with the measured detonation parameters serving only as a measure of the quality of the explosive. The major drawbacks with this approach are discussed, in view of the non-ideal nature of commercial explosives and the field conditions prevalent during the blasting operation. A unified approach to rating explosives on the basis of blasting performance rather than calculated energy alone is presented for various types of explosives. This incorporates the relevant field parameters as well as the effect of non-ideal reactions, both of which affect explosive energy release and its transfer to target rock.

Jan 1, 1988

By Charles A. Kliche

The Comprehensive Environmental Response, Compensation and Liability Act of 1980 (CERCLA) established a national program for responding to releases of hazardous substances into the environment. The funding mechanism for this program is the Hazardous Substance Response Trust Fund (commonly referred to as Superfund), which provides funding for the implementation of removal and remedial response actions.

Jan 1, 1997

By John Turner, James Lamb

The Minnesota Department of Transportation (MNDOT) has an extensive project to improve driving conditions and reduce hazards to motorists on US Highway 61 between Duluth, MN, and Canada along the north shore of Lake Superior. In 1991, the Lafayette Bluff Tunnel was completed just north of Two Harbors, MN, through a joint venture of Johnson Brothers Corporation of Litchfield, MN, and Obayashi Corporation of San Francisco, CA.

Jan 1, 1994

By Raymond M. Dixon, Dale L. Ramsey

Upon being introduced to the MAGNETIC COUPLING concept,Balsinger,Inc. wanted to conduct field trials to explore the potential of Magnetic Coupling in the U.S.. Although the Magnetic Coupling Concept has been widely used, the U.S. proposed blasting criterion not previously addressed by the system. Modification to the system assembly and blasting accessories had to be made to make the system adaptable to our specific requirements. The field trials and system modifications are the basis of this paper.

Jan 1, 1990

By H Y. Fang, H Sutherland, R M. Koerner

Due to the increased number of complaints by property owners to blasting related industries an apparent need for a clearer understanding of blasting-related damage is needed. We feel that direct structural crack monitoring during such blasts is the appropriate measurement technique. Instrumentation and interpretation of results for taking such measurements are described in this paper. Typical results from blasting and other environmental effects are also described which can eventually be related to Fracture Mechanics principles in the hope of clarifying such disputes in an equitable manner.

Jan 1, 1976

By David Leidel

A major characteristic that distinguishes modern society from its predecessors is the understanding that events are not driven by the whims of the gods, pre-ordained fate or nature, but are controlled to a greater or lesser extent by the actions, (or inactions), of people. The study of risk assessment is the basis for determining risk or the likelihood of an event occurring combined with the consequences of that event if it does occur. This study is indubitably linked to the mathematics of probability and statistics which permits the quantification of risk. As the Industrial Revolution significantly increased the exposure of persons to new types of energy sources, materials, equipment, and means of more rapid transportation of goods and people, quantitative risk assessment became a vital tool in protecting workers and the general public exposed to these new technologies.

Jan 1, 2007