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By Frank Huber, Ed Fulop, Neil Singh, Ron Elliott, Blair Gohl, Lewis Clarke

This paper covers the successful application of explosive compaction technology for the densification of the foundation soils for the seismic upgrade of the Seymour Falls Dam, Vancouver, BC. The original earthfill embankment constructed during 1958 to 1961 was upgraded in 2004 to 2007 to withstand the effects of a maximum credible earthquake. This paper provides general background information on the theory of the explosive compaction of soils, history of use, geology of the site, project constraints, explosives selection, blast designs, instrumentation used, problems encountered and solutions implemented, and the results achieved.

Jan 1, 2009

By Roger Favreau, Patrice Favreau

Without blasting there can be no roads, no hospitals, no factories, not even foundations for homes. Yet in 1960 the only way to design a blast was by trial/error. By comparison, bridges were already designed by calculations before being actually built. This was possible because equations based on the fundamental principles of science existed with which all the stresses in the bridge could be calculated. In 1960 no equations based on the fundamental principles of science existed with which the mechanisms that take place inside the rock mass during a blast could be calculated. Since then the main author made it the objective of his research to seek such equations, and to validate that they gave accurate answers by means of experiments in the field, experiments made in co-operation with mines, quarries and the explosives industry; results have been reported in some 90 publications.These equations now deal with essentially all aspects of a bench blast: the intensity of the shock wave and the fragmentation size distribution throughout the rock mass; the movement of all the fragments into the muck pile; the fly rock and vibrations from the blast; etc.; are presented examples of such equations. They are now assembled into a computer simulator called Blaspa accessible on the Web, with which one can design a blast just as a bridge is designed. An example is presented. The reason to design a blast by simulations rather than solely by trial/error is that if it leads to damage, it is only after the actual blast that the blast design is realized to cause damage. If however the blast design had been simulated before the blast, then the risk of damage is identified before the blast and is prevented by redesigning the blast. Examples of such situations are presented. The need to a void damage is very necessary because the public is becoming opposed to blasting. When a blast does cause damage, and people learn that the blast was designed solely by trial/error even though simulation was available and would have prevented damage, they become even more strongly against blasting; they may succeed in getting a quarry closed. Their objections to unchecked blasting are not unreasonable, especially as simulating a blast with Blaspa on the Web is a very simple procedure.

Jan 1, 2013

By P A. Lang

Canada is constructing an Underground Research Laboratory as part of a comprehensive program to evaluate the concept of nuclear fuel waste disposal deep in stable rock formations. Careful blasting methods have been designed and quality control procedures have been used for the excavation of the access headings in the underground facilities. This paper describes the work done between 1984 December and 1986 December at the second level, 240 metres below surface.

Jan 1, 1987

By Leslie Taylor, Uli Leiste

In this paper, results from small scale testing conducted to determine pressure time profi les acting on a plate (taken to represent the bottom of a vehicle) at any given distance from the center of the plate will be presented. These results will be discussed in relation to visual observations of the upward moving sand.

Jan 1, 2008

By Bilegt Batbold, Bayu Saputra, Chris Batten

The ability to fire multiple blasts simultaneously can provide significant benefits to any open pit mining operation. Reduced blast-related downtime by reducing blast events can increase equipment utilization and maximize material movement. Significant sequencing benefits can also be delivered, associated with reduced equipment relocation. This paper describes the work completed in partnership between Orica and Oyu Tolgoi to successfully demonstrate that combined production-trim and midsplit blasting could be implemented successfully while successfully managing the risk of increased damage to the final walls. The paper details the methodology used to assess key performance measures linked to final wall damage and compares the performance between the following blasting methods. • Free face trim blasting vs. combined production-trim blasting • Presplit blasting vs. midsplit blasting. The results of the initial trial blasts are presented, along with the method agreed by the key site stakeholders for ongoing application. The method used to keep the risk of final wall damage to an acceptable level is explained, along with the benefits delivered to Oyu Tolgoi operations associated with the initial 12 months of application.

Jan 21, 2025

By David Lilly, Robert Ethier, David Bremer

The Lafarge Ravena Cement Plant in Ravena, New York demonstrated continuous and extraordinary improvement in productivity during the past several years. The factors driving continuous improvement at the Lafarge Ravena Plant include: 1) Management techniques including regular scheduled and effective Blasting Optimization Team meetings. 2) A real time blasting database to guide blasting product and procedure decisions. Key decisions involved all levels of quarry and blasting supplier personnel and a close working relationship between production and blasting areas of expertise was demonstrated. 3) Blast optimization and optimization of quarry operating parameters such as blast location relative to crusher location, hours worked, etc.

Jan 1, 2007

By Thomas M. Keevin, Gregory L. Hempen

A user-friendly model for environmental effects from underwater explosions is presently available. The model by Munday et al. (1986) is effective for determining fish mortality radii from underwater shooting. The IBLAST program (Coastline Environmental Services 1986) from this model includes estimates for both borehole-loaded explosives for demolition or rock removal purposes and midwater shots. Midwater shots may be used for fish population assessments or some seismic surveys. The program produces approximate mortality distances for planning purposes. IBLAST does have serious shortcomings of which users should be aware.

Jan 1, 1995

By Sterling Ziegler, Kameron Ray

Mining operations at a Wyoming coal mine were progressing to within 300 feet (91 meters) of a high pressure natural gas pipeline. Vibration levels from cast blasting were at a point at which standard designs would exceed permitted limits and could potentially damage the pipeline. Without a confident vibration model, mining would be unable to continue in the pit rendering an entire cut of otherwise mineable coal sterile. To safely blast in the area, linear superposition seedwave analysis techniques were attempted to be used to create a model that could accurately predict the vibration at the pipeline. Four signature holes were fired individually. The four signature waveforms were monitored at eight discrete locations to create thirty-two vibration data points. Two of the monitors were equipped with triggers enabling the calculation of p-wave velocity.

Jan 1, 2018

By J. P. Proulx, Richard O’Meara, Ruilin Yang

A blast optimization project was carried out at an Open Pit Metal Mine using the Multiple Blasthole Fragmentation (MBF) Model and the Multiple Seed Waveform (MSW) blast vibration model. The aim of the project was to optimize rock fragmentation of the ore blasts to significantly increase metal recoveries while keeping the blast vibration levels at the highwall under control. The project also examined the blasts in the waste rock using the Fragmentation model to expand the blast pattern and select economical explosives for drill and blast cost savings while minimizing any adverse effect on the dig rates. Two sets of near field signature blasthole tests were conducted in both hard ore and relatively soft waste rock. The information from the near-field signature blasthole vibration was used as input to both the MBF and MSW models, as site specific geological information interacting with blasting. The implementation of the full blast design is also input to the MBF and MSW models. A production blast for each rock type was monitored for blast vibration and rock fragmentation. The full blast information and the blast results are used to calibrate and validate the models. The Fragmentation and Vibration model were established for the two rock types at the mine. At each site the Fragmentation modeling was conducted in parallel to the Vibration modeling to ensure blast vibrations were under control while the rock fragmentation was improved. The Fragmentation MBF and MSW are each an integral part of the blast optimization tool. Various scenarios using different explosives, hole delays and blast patterns were modeled for rock fragmentation and blast vibration. The recommendations from the modeling project were to be field trialed at the mine. The implementation of the recommendations was expected to help the mine significantly in terms of the mining economics, and high wall stability and safety.

By Francisco Sena Leite, Vinicius Miranda

Mine blasting is directly associated with ground vibration. If these affect critical structures (buildings pit walls, etc.) they must be mitigated to reduce the environment and social impacts. Vibration monitoring and control is one of the most important procedures in blasting because it will impact short and long term incidents associated with this blast effect. Technology moves ever forward, and today we have personal devices that are equipped with an array of sensors, for that reason the authors decided to investigate the possibility of using a personal device to do vibration control. This case study compares the same blast measured with a traditional seismograph and a smartphone. To validate this new methodology, attenuation laws were built with data from a traditional seismograph and a smartphone application. Predictions were also made prior to a set of blasts. Residual analysis was used for data validation from the two different sources. From the performed analysis, to prove the validity of this new methodology, the normality tests for statistics residues analysis proves that it is possible to infer that the model has a null residual mean and a small residual error. The achieved results show the accuracy of these devices, the authors pretend to show the potential of this equipment and open a completely new door for vibration analysis.

Jan 1, 2018

By Adrian Moore, Alan Richards

A real-time system for prediction of the effect of meteorological conditions on airblast overpressure levels has been established in the Hunter Valley Coalfield in Australia. Real-time meteorological data from continuously operating sounding equipment and a predictive meteorological model is input to an atmospheric refraction model that enables the effect of meteorology on airblast overpressure levels in the area surrounding the blast site to be evaluated. Graphical outputs from the model, which are superimposed over a scaled airphoto of the mine and surrounding area, show the extent that airblast levels will be increased. When combined with inputs that quantify the effect of blasting specifications, the airblast levels that will result in the surrounding area from the combined effect of blasting specifications is determined. The model permits those responsible for blasting to make more accurate decisions on suitable times that blasting may take place to conform with applicable airblast limits.

Jan 1, 2009

By Thomas H. Kleine, Alan R. Cameron, William W. Forsyth

In general the software required by a blast designer includes tools that graphically present blast designs (surface & underground), can analyze a design or predict its result, and can assess blasting results. As computers develop and computer literacy continues to rise the development of and use of such tools will spread.

Jan 1, 1995

By Italo Onederra, Jason Furtney, Ewan Sellers

The Hybrid Stress Blasting Model (HSBM) is a high level blast modelling research tool which provides results that can still be used implicitly for practical blast design. The code is being developed through an international collaborative research project funded by a consortium of companies which is comprised of explosive, equipment suppliers and major mining houses. A key component of the HSBM is the numerical code and user interface designated as Blo-Up 2.5. To date validation work has focussed on breakage, fragmentation and damage outcomes in controlled laboratory experiments and using large concrete cubes

Jan 1, 2012

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 F. Malek

An extensive blast monitoring program has been carried out to study explosive performance and the effectiveness of blast designs in production blasts in a deep underground mine. Comprehensive monitoring of blasting vibrations through multi-station high-capacity high-frequency accelerometers, and borehole deformation history have been the main tools of such analysis. The mining activity involves relatively unstressed stopes as well as highly stressed stopes. More than 30 production blasts have been monitored, and the respective vibrations from close-range as well as distant seismic stations have been analyzed, and the vibration parameters (amplitude and frequency) have been correlated with explosive charge weight in the holes. It is found that the correlation between blasting rounds and the corresponding vibration amplitudes often have poor correlation for a very significant portion of the blasts. These point to either explosive charge malfunction in those specific blast holes, or inadequate blast design, or the effect of high in-situ stresses, or any combination thereof. This paper analyzes these variables and their effect on the overall blasting operation at the mine.

Jan 1, 2013

By D Wilson, E Nagy, R A. Augsten, R R. Vandebeek, R L. Guilbeault

The Canadian Explosives Research Laboratory (CERL), is evaluating the status of the Schedule IV explosives container as it presently pertains to the industry. The Schedule IV container serves the same purpose in Canada as the IME 22 container does in the United States. That is, to transport detonators on the same vehicle which is carrying explosives.

Jan 1, 1990

By A. Ribeiro

The effective utilization of resources and process optimization play a crucial role in the sustaining and growth of overall businesses. This principle holds true in the mining sector, where particular attention is required during the comminution steps. This necessity arises from the fact that mining operations often consume substantial amounts of energy in mineral processing. Therefore, it becomes imperative to thoroughly study the integration of comminution steps. In many instances, an approach to be studied is the operation commencing with the drill and blast phase and culminating in the grinding product process. Nevertheless, establishing an optimal integration between drill and blast operations and the grinding phase is a complex undertaking due to the direct influence of rock characteristics on this process. And in many cases, the complexity and variability of such physical characteristics makes mining operations to ignore such influence. Consequently, Enaex Mining Technical Solutions (EMTS), in collaboration with Lundin Mining's Chapada Mine engineering team, and with the assistance of Hatch Consulting and Technology, has undertaken a comprehensive study aimed at enhancing mill throughput at the Chapada operation. The basis of this study lies in characterizing the rock masses present in the Chapada Mine to gain a deep understanding of the material that needs to be comminuted. Subsequently, the mineral processing team determined the most suitable size distribution for the Run-of-Mine (ROM) material. With this information, the drilling and blasting team built a site-specific blast fragmentation model, able to simulate various blast design scenarios. This approach enabled to optimize the utilization of available drilling and blasting resources while striving to achieve the optimum ROM characteristics. Since 2021, the Mine to Mill methodology has been progressively implemented at the Chapada Mine. As a result, the blasting engineering team now utilizes the blast plans generated by the fragmentation model simulations as a foundation for designing blast plans that align with the operational and financial capacities of the mine. Overall, it was predicted that this implementation could lead to an average increase in mill throughput of 13-22 % depending on blend feed, once all recommendations are implemented. Even with partial implementation, plant results demonstrate a 5 % increase compared to the period before the Mineto-Mill project, without any coarsening of the associated grinding product size.

Jan 1, 2024

By D. Johansson, C. San Miguel, U. Stenman, N. Petropoulos

Blasting is a commonly utilized method in civil engineering projects and mining operations. Ammonium nitrate-based (AN-based) explosives are the most efficient explosives today in terms of handling and performance. However, a side effect is the production of gases. The reduction of these gases plays an important role in the safety and environmental aspects in the working place. Therefore, optimizing the recipes of explosives is vital for minimizing the environmental impact and increasing performance. The aim of the project is to provide results and recommendations on the use of emulsion commercial explosives to support the Swedish mining industry and tunnel-contractors as well as the explosives manufactures. The approach was to test various recipes of civil emulsion explosives to investigate the generation of toxic fumes (CO, CO2, NO, NO2 and NOx) during their detonation. To further increase the knowledge of the influence of different additives, ammonium nitrate prills were added in various percentages. The experimental configuration consisted of magnetite mortar cylindrical specimens with a 50 mm borehole at their center, filled with emulsion explosive. Several tests with different emulsion compositions regarding ammonium nitrate additives (10%, 20%, 25%, 30% and 35%) were carried out in a blasting chamber. The measurement equipment was composed of a flue gas analyzer. The instrument was meticulously cleaned after every test, as well as before and during the tests due to condensation (high humidity and dust) at the inlet of the instrument. The emulsion was manually sensitized with microballons and pumped into the cylinders to ensure lack of bubbles, which could introduce inhomogeneities. The acquired gas concentration data was complemented with temperature, humidity, and VoD measurements. The results showed a linear increase of nitrogen gases as the percentage of ammonium nitrate prills increased. On the other hand, carbon gases had a relatively low coefficient of determination. The VoD data showed a behavior that can be described with a simple quadratic equation.

Jan 1, 2024

By C. Liley

Open cut blasting at the Ernest Henry mine has the potential to cause damage to nearby underground workings. This paper is a case study of the blast vibration management project which was conducted to ensure pit blasting did not adversely affect the stability of upper production levels or cause damage to the underground primary fan units.

Jan 1, 2012

By Greg J. Stach, Norman "Skip" Hale

The authors describe the development of an overburden blast casting program in the upper seam of coal at a 2-seam surface mining operation on property adjacent to an active operating underground coal mine. Control of vibration is essential.

Jan 1, 1984