Search Documents

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 X. Gumede

A model is being developed to quantify the benefits for mining houses resulting from the reduction in greenhouse gas and energy consumption by the application of innovative blast designs in addition to direct financial benefits throughout the mine to mill value chain. The conversion from shock tube initiation systems to electronics and some changes to powder factor measured on an open pit mine had previously been used to show significant improvement on blast outputs. Benefits were realised on drilling, blasting, loading, hauling and beneficiation. Quantification of the relationship between powder factor and reduced greenhouse gasses is investigated in this study. The study has highlighted new data that must be recorded and hence some assumptions were made as to fuel consumption and the energy in crushing was obtained from the Bond work equation. The mine to mill projects in an open pit platinum mine and a quarry produced energy savings and reduced greenhouse gas emissions associated with the careful application of explosives and blast innovations. The less fines project showed an increased carbon footprint. The model provides a new insight into how project feasibility should be decided based on economic and environmental viability.

Jan 1, 2012

By S A. Steyn, P Terrett

Air decking has become a widely practised method internationally for modifying fragmentation results and providing cost savings from reduced explosive consumption. Duvha has been applying air deck technology to overburden and midburden blasting for a few years. A thorough evaluation of air decking at Duvha has been made by instrumenting a number of blasts and analysing costs from direct savings in reduced explosives costs to savings in improved dragline productivity.

Jan 1, 1995

By Michael Wieland

The work principle from thermodynamics is used to model the shock and heave for explosives shot in rock or under water, with the latter compared to reported results. The work principle utilizes restrictions and constraints to yield a representative fit to the irreversible (natural) shooting process. The reduction of the internal energy of the reaction-zone yields the total expansion work (TXW), the resultant sum of the rock/water shock and heave. The restoration technique of forming a closed thermodynamic loop yields the reversible mechanical work (RMW) or the rock/water heave. The residual work that remains when RMW is subtracted from TXW yields the irreversible disorder work (IDW) or the un-dissipated (without loss) shock in the surrounding rock or water. The work principle renders an unequivocal relationship for the shock-loss factor, rather than the traditional roundabout formula for correcting the underwater gauge-shock of un-modeled explosives. There’s a novel heave-ratio factor that unquestionably rates the fit of results under comparison. Rock-shots are more complex in nature than underwater shots due to rock fracture and stratum rupture, though numerical resolution is worthwhile. The proposed rock-water-jelly (RWJ) model yields rough estimates, with rock-type results not wholly different from their underwater counterparts. Though reported underwater shots reveal shock and heave trends with respect to charge formulation ingredients, there are no such rock-shot results for comparison, since the relevant test measurements in rock remain difficult, if not intractable.

Jan 1, 2007

By N. Powell, P. Hunt, A. Wetherelt

This paper considers the current methods of analysis employed, the validity of assumptions made and the reliability of results and predictions derived; where appropriate, alternative methods are proposed which are more accurate and can be applied with greater confidence. In regard to data collection, new local blasting data has been analysed and conclusions drawn but, due to the restricted amount of space available, reference to data set A only has been made in the text. The problem of mathematical model choice is considered and results for two and three parameter power laws are compared. The very important matter of parameter determination is discussed fully, with major emphasis being placed on the comparative merits of log-log linear, log-log planar and direct power law regression. Supporting data analysis examples are included. Assumptions regarding the normality of ‘best-fit’ regression model residual distributions are questioned and the reliability of associated safety limit determinations is discussed.

Jan 1, 2003

By Thierry Bernard

Since the signature hole method principle has been described in the 80's, there has always been a lot of controversy about it. The theory is easy to understand but when it comes to apply it for predicting vibration level, optimizing timing to reduce PPV or shifting frequencies, it’s not always working as expected. Simulations show waveforms that don't make any sense or predictions that are far away from actual results.

Jan 1, 2012

By John Atkinson, Steve Repola

This paper will describe two blasting plans that have been developed for American Aggregates' Marble Cliff Quarry located near Columbus, Ohio. Two different limestone formations are mined on different levels of the quarry. Each formation requires a different blasting plan which address vibration considerations, crusher productivity, drilling and blasting costs and adjacent neighborhood concerns. Controlled blasting is critical to continued mining operations in this Midwest urban setting.

Jan 1, 1993

By Ran Tamir

"This document introduces the use of drone generated aerial photography to collect and analyze fragmentation data for both muck piles and post crusher stockpiles in order to support the continuousimprovement process. In tandem with photo analyses software, drone imaging gives mines and aggregate sites a fast, accurate and economical method of benchmarking and optimizing the process of size reduction to spec."

Jan 1, 2017

By Shazad Hosein, Rob Farnfield, Bill Birch, Liam Bermingham

The propagation of a shock wave through air as a result of quarry blasting consists only of one type of wave, the compression wave. This is in marked contrast to seismic waves where a number of different types of wave are generated by the one blasting event. Even so the interaction of the burn time of a single hole and the resulting air overpressure is still too complicated to be able to be accurately modelled from first principles. It is considered that the best way forward is to monitor an individual single hole to obtain a signature wave form that has resulted from this complex interaction. Once this wave form is known, the variation in geometry of a mutli-hole blast and the timings of the successive detonations can be modelled to give a sufficient degree of accuracy to recreate the likely magnitude, duration and wave form of a multi-hole quarry type blast. This can then be directly compared with actual air overpressure wave forms from quarry blast to verify the model.

Jan 1, 2012

By R. Alford

In the modern world of demolition safety is paramount and unnecessary or unquantifiable risks are not accepted (FasterCapital, 2024) and all risks must be kept As Low As Reasonably Practicable (ALARP) (BSI, 2017). This principle has led to a huge reduction in deaths in the last 50 years and the statistics continue to improve although this is starting to plateau (Beal, 2007). Under normal circumstances, this is now simply part of the normal way work is done and systems are in place to ensure both safety and economic profits are assured. What happens when the environment is less controlled and risks are unknown, such as after a natural disaster, war, an accident or a stand-up from a failed demolition attempt? A dangerous structure cannot responsibly be left alone with a fence around it so some action must be taken, but how can this be done safely and responsibly? An incident in Didcot, England in which half of a power station’s boiler house being prepared for an explosive demolition collapsed suddenly, killing four men in 2016 provides a useful case study of how technology, creativity and planning can be used to conduct complex demolition fully remotely to avoid any further risk to life.

Jan 21, 2025

By Timothy Stark

Blasters are usually strictly liable for injury or damage caused by flyrock (trespassory invasion) and blast-induced vibrations (non-trespassory invasion). The application of strict liability to non-trespassory invasions has resulted in significant litigation that has hampered the use of blasting and the blasting industry. Stark (2002) proposes that blasters should not be held strictly liable for non-trespassory invasions but should be liable only if their conduct is proven to be negligent. This change in legal standard was proposed because improvements in blasting technology over the last thirty years allow blasting to be conducted without substantial risk of harm to property and thus the amount of harm imposed by a blast can be related to the level of care exercised by the blaster. It is anticipated that a negligence standard will reduce the amount of litigation because a plaintiff will have a greater burden to overcome. To facilitate the acceptance of a negligence standard by a court of law, this paper summarizes the standard of care using the 1977 Surface Mining Control and Reclamation Act, extensive U.S. Bureau of Mines research, and current blasting techniques, such as blasting mats. It is important for the blasting industry to promulgate a standard of care so a judge can feel confident that blasting can be routinely and systematically controlled and if the legal standard is changed from strict liability to negligence a subsequent judge or jury will be able to evaluate the level of care exercised by the blaster. This paper also suggests that the industry and/or ISEE develop and disseminate a comprehensive standard of care that courts can use to further justify a change from strict liability to negligence and evaluate the standard of care.

Jan 1, 2003

By Stephen Mansfield, Johannes Schoeman

In August 2006 a technical alliance was formed between Orica Mining Services and Century Mine to provide blasting solutions. The alliance is in the form of a Rock to Specification (R2S™) service, one of Orica’s Blast Based Services (BBS™). The ultimate goal was to facilitate the rapid expansion of material movement from 26 to 41M m3 (34 to 53M yd3) per annum while maintaining a reliable ore supply to the mill.

Jan 1, 2010

By Thomas M. Keevin, Gregory L. Hempen

Natural resource agencies, under various regulatory authorities, are challenged with permitting underwater explosive use while at the same time protecting aquatic resources. Deciding on whether or not to allow use of explosives requires striking a balance between development and aquatic resource protection. A company's goal in underwater explosive use is to select methods that are both expedient and cost effective. Use of explosives is often the best alternative for engineering reasons or economic considerations. Over and above legal requirements, indiscriminate destruction of fish and other aquatic resources is not in a company's best interests because of concerns relating to public image, as well as the need to secure future contracts.

Jan 1, 1995

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 Baohua Guo, Xuelin Yang, Tingkan Lu, Hailin Sun

The work presented in this paper mainly involves two parts. Firstly, the fundamental characteristics of the high pressure carbon dioxide gas fracturing technique (CO2 technique), including, a proposed method of TNT equivalence calculation, which is used to calculate the TNT equivalence of discharge of CO2 technique, and the comparison of the explosion volume generated by dynamite and expansion volume of liquid carbon dioxide is conducted to show the differences of fragmentation capacity between the two of them. Secondly, the coal seam fragmentation mechanisms of CO2 technique are proposed, including, 1) Gas jet cutting and penetration by shaped charge, 2) Gas volume expansion by changing phases of carbon dioxide, 3) Coal seam softening by destress blasting and 4) Coal seam fragmentation by discharge vibration, associating with the mechanisms, the equations for calculating fragmentation radius are developed and verified.

Jan 1, 2017

By Yong Pan, Purushotham Tukkaraja

Block caving is a preferred underground mining technique due to its high production rate and low operation cost. Before its final step into a mature caving system using gravity to break rock, drilling and blasting are required to form drawbells to connect the production level and undercut level and induce the initial caving propagation in undercut level. A large amount of toxic fume generated by blasting activities poses a big threat to people working in a confined environment and ventilation is assumed to be the most economical and efficient way to deal with this issue. Past research shows that it’s common to use traditional methods like using a formula or using numerical method (Computational Fluid Dynamic (CFD)) simulation to predict re-entry time after each blasting, but it fails to consider the percentage of toxic fume entrapped in muckpile, which could reach up to 70%. In this paper, CFD was used to investigate the blasting toxic fume characteristics under different entrapping percentages and under changing muck pile properties like broken rock size and porosity. It showed that CFD was a very useful method to study blasting fume in an underground mine and it took much longer time to dilute toxic fume into a safe level with higher entrapping percentage. The dilution time increased with a decrease of broken rock size and porosity.

By Behrouz Ohadi, Kamran Esmaeili, Bibhu Mohanty

In most metalliferrous open pit mines with heterogeneous orebodies, blast-induced rock movement is a crucial outcome that has unfavorable impact on ore and waste segregation in the post-blast muck pile, resulting in either ore loss (the ore is misclassified as waste and sent to the waste rock dump) and/or ore dilution (waste is misclassified as ore and sent to the processing plant). While many studies have been carried out to assess the influence of blast design parameters on blast-induced rock movement, the influence of rock mass characteristics in these studies have been overlooked.

Jan 1, 2018

By C. Aimone-Martin, C. Dowding, M. Jern, J. Gjødvad

This article compares percentages of compliance for six national standards to demonstrate how these standards vary on-site in a real project. This, to the best of the authors' knowledge, has not been accomplished before. Different standards not only vary in allowable amplitudes of induced vibrations but also in how they are measured (transducer location, transducer orientation, frequency content of vibration, etc.). Thus it is not straightforward to compare the permissible values of induced vibrations with each other. This challenge of comparison is overcome in this project by instrumenting a structure with multiple transducers according to different national standards and comparing the degrees of compliance. Compared herein are compliance with standards used in United States of America, Germany, Great Britain, France, Austria, and Sweden. Averages of the percentage of compliance and ratios of measured vibration amplitudes for all six national standards are compared both in tabular and graphical form for 20 blasts at the Aitik mine northern Sweden. It is the largest open pit mine in Europe and blasts are atypically large with more than 1000 kg charge per hole and several hundred holes per blast, lasting 3-5 seconds. Results show that percentages of compliance can vary by as much as 2 to 75 % for these blasts at this structure. The overall project is a cooperative effort between EFEE (European Federation of Explosives Engineers) and ISEE (International Society of Explosives Engineers), supported by more than 17 persons from 8 different countries. At the present the experts are the four authors of the present paper and Dr. Robert Farenfield, Dr. Nathan Rouse, Douglas Rudenko, Brent Meins, Kenneth K. Eltschlager, Karin NorénCosgriff, Travis A. Davidsavor, Vitor Luconi Rosenhaim, Johannes Kutschera, Bernard Thierry, Thomas Moser, Cory Loukedis, and Keith Best. The project began with a literature study and a survey including an evaluation of the answers provided by members of EFEE. Results were presented at the ISEE conference in Denver 2020 as well as the EFEE conference in Helsinki in 2019 (Gjødvad & Jern, 2019; 2020). The second part of the project was initiated in May 2021 with installation of 7 seismographs from two different manufactures, 3 cracs gauges and 2 microphones on a building at the Aitik mine in northern Sweden. The third part of the project has moved to the United States. Two residential structures adjacent to quarries are being monitored in Michigan and Ohio. Installation and monitoring began in March 2023 and are expected to continue for 6 to 12 months. In addition to the objectives of phase two the 2023 study includes calculations of global wall strains from measured velocity time histories and measurement of response of existing cracks to vibratory and climatological effects

Jan 1, 2024

By Tristan Worsey

This work was performed during the summer of 2008 during the junior year of a BS in Mining Engineering. It was observed that the mine was having a problem with back break during the blasting of development drifts. The unwanted back break was causing the mine extra costs in ventilation, ore dilution, ground support, back fill, explosives and man-hours. The blasting practices were observed for four weeks and the problems and their solutions were defined. In this paper the reasons and causes of the problem are explained with the proposed solutions to eliminate back break.

Jan 1, 2010

By Hector O. Romero, Paulo C. Fernández A, Christian Rees Prado, Claudio C. Gajardo

In open-pit mining operations, the presence of remnants from past underground labors represents a significant operational challenge, especially if they are in the surroundings of high-grade zones. The existence of uncrushable elements, such as metallic support fragments of abandoned equipment, can trigger critical operational issues if they reach conveyor belts systems or primary crushers, jeopardizing the mine to plant operational continuity. These kinds of incidents lead to expensive unplanned shutdowns, the increasing of corrective maintenance events costs, and risk to meeting expected production results. This work demonstrates the application of a three-dimensional numerical modeling tool for simulating rock displacement post-blasting (by integrating key design parameters, such as blast pattern design, detonating times, charge distribution and pre and post blast surveying). The study was conducted at Andina Mine, operated by Codelco, Chile, and enabled the identification and zoning of areas with potential presence of underground hazards in displaced rock mass, using historical data from previous workings and geotechnical mapping. The displacement results were compared to the actual post-blast surveying, ensuring an acceptability level above 80%, considering both fully confined (bank opening) and free-face blasts. Additionally, this approach allows the determination of an optimal safety offset, initially set at 10 meters and currently under validation for potential reduction. The results supported the determination of safe extraction zones and the design of excavation, loading, and haulage strategies from mine to plant or stockpile, ensuring 100% reliability in the segregation of high risk materials. Implementing displacement simulations underscores their relevance in operational risk prevention and mitigation, adding value to short-term mine planning and strengthening the safety, efficiency and profitability of the open-pit mining production process.

Jan 26, 2026