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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 Dale S. Preece, J Paul Tidman, Stephen H. Chung

"A discrete element computer program named DMC-BLAST (Distinct Motion code) has been under. development since 1987 for modeling rock blasting (Preece & Taylor, 1989). This program employsexplicit time integration and uses spherical or cylindrical elements that are represented as circles in2-D. DMC-BLAST calculations compare favorably with data from actual bench blasts (Preece et al,1993)."

Jan 1, 1997

By Brandon Axelrod

This paper follows a student’s interest in explosives which began at an early age after watching a television program highlighting explosives engineering. The use of explosives in those programs led to curiosity about how one gets involved in the industry. These programs enticed the author to further investigate the explosives industry leading him to an explosives camp for high school students. After attending the camp, this passion further developed into postsecondary education.

Jan 1, 2015

By Gary L. Self, Ronnie Daniel

With the advent of large scale blasts utilizing overburden casting techniques, it was imperative that an ultra reliable surface delay system be developed. Shock tube and detonating cord surface delay systems have been hampered by the lack of a reliable easy-touse method of incorporating multiple paths of initiation to each hole. Two new redundant nonelectric delay systems have been developed utilizing multiple signal paths to allow a higher degree of safety and reliability. The first system designed uses a combination of detonating cord and nonelectric shock tube delays to allow multiple delay paths to each hole. The second system incorporates a new all shock tube delay system which allows multiple delay paths while minimizing over-pressure by eliminating detonating cord trunk lines. These two redundant systems have been used in over 500 production blasts without any misfires due to surface cut-offs or detonator malfunctions.

Jan 1, 1989

By Peter Moser, G. Reihholf

Holcim, one of the world's leading suppliers of cement, aggregates and concrete, has set up a few years ago a working group “Quarry” in order to optimize the performance of its central European quarry operations in terms of work safety, environmental standards and economic performance. One of the activities of this working group "Quarry" addresses the subject of blast fragmentation in the quarries. A benchmark study of the blast work in all quarries has shown substantial differences for the various operations in terms of drill& blast costs. Especially big differences were found with respect to the drilling patterns as a function of the borehole diameters and with respect to the utilization of the borehole volume for charging the explosives.

Jan 1, 2006

By Jean-Sébastien Lambert, Serge Roberge

"At the end of 2014, Holcim Canada (Demix Aggregates Division) considered the possibility of drillingand blasting a big volume of rock in order to expose a high-quality limestone bench in one of their urbanarea quarries in Laval, Quebec (Canada). The project includes many challenges and has thus been qualified as a high-risk operation."

Jan 1, 2016

By Charles Zdazinsky

Over-break is undesirable in underground civil construction because it excessively damages rock along the perimeter of the tunnel, which directly influences the cycle times of advancement. A quicker cycle time for each process is required to optimize the operation and therefore minimizing over-break is essential for operational success.

Jan 1, 2015

By Dr. Anurag Agrawal, Steve Franklin, Clint Zimmerman, Elijah Williams

In a time when data has become a highly valued commodity within many mining and quarry operations, managing large amounts of current and historical information can be difficult. If not managed properly, trying to leverage the data to make informed operational decisions promotes another challenge. Geographic Information System (GIS) is an environment that uses computers and software to create, manage, analyze, and map all types of data. Currently, the mining industry is faced with a challenge to produce the demanded critical metals and minerals that drive our economies. GIS is leveraged in many large mining industries today to help drive decisions, save cost and plan for future operations. Specifically in the Drilling, Blasting and Quarrying industries, data is being captured at many different levels, whether it is a subsurface geological, blast performance, quarry surveys, loading and hauling, or crushing performance. Pen and paper logs and reports compiled lack the dimension that GIS can bring for extracting value from real-time or historical data. GIS connects data to maps, integrating location data with all types of descriptive information. Paired with Artificial Intelligence, additional analytical layers can be built on platforms to extract data and automate workflows. Having the ability to encompass several forms of collected data to drive operational decisions can bring huge savings to the bottom-line. This paper will dive into the areas where GIS data can drive value into operations by assisting in the management and analysis of the types of data being captured, specifically with Drill and Blast. Whether it is tracking haul road conditions, monitoring locations of equipment, environmental conditions, quantifying blast performance or developing a quarry plan based on geological models. GIS can collectively encompass all of this data to bring tremendous value to the operations, improving safety, efficiency and production.

Jan 21, 2025

By Seokbin Lim

In the design of explosives devices, an understanding of the behavior of explosively propelled matter is one of the most important steps in maximize the performance of these devices. For instance, an explosively driven metallic liner in LSCs (Linear Shaped Charges) creates its functional effect of penetration after a finite distance of travel (before collapse), thus the detailed study of the projection mechanism of the flat liner after detonation helps in the optimization of the design of LSCs. In a typical metallic flyer driven by explosive detonation, the detonation gas propels nearby matter including flat flyers. After a certain degree of expansion in the detonation gas, the flat flyer reaches its maximum velocity and slows down afterward. These typical behaviors are well investigated and numerically studied by many researchers. However, the rarefaction intrusion (detonation gas expansion) near the surface of the explosive charge creates significant deformation of the flat flyer , and produces U-shaped bending or deformation near the edge of the flyer during projection, creating unexpected behavior in explosive devices of interest. In this paper, a preliminary investigation of a localized Ushaped deformation of flat metallic flyers during projection is studied utilizing a theoretical approach and computational modeling facilitating an understanding of a general tendency of the deformation behavior.

Jan 1, 2010

By John H. Weigand, Stephen V. Crum

"VIBRONICS, INC. instrumented and monitored a residential structure for response to,blasting at aMidwestern surface coal operation. The residence was owned by the mining company and was extremely close to the operation. Blasting was conducted within 120 feet (36.5 meters) of the test structure. Up to seventeen (17), four (4)-channel seismographs were used during the monitoring period. The basement walls and floor were monitored. VIBRONICS, INC. also monitored a brick chimney in the basement and attic. Structural responses were then compared to outside vibration measurements taken in the soil near the foundation."

Jan 1, 1998

By B Mohanty, R Deshaies

Initiation of small diameter explosives by sympathetic shock pressure in water has been investigated under controlled laboratory conditions. Changes either in the geometry of the donor explosive or its point of initiation can alter the essential characteristics (amplitude and duration) of the resulting shock pressure pulse. The pressure signatures from both spherical and cylindrical explosives donors have been studied, in water as well as in various explosive matrices. This paper summarizes the investigations carried out with both 'primed' and 'non-primed' slurry and emulsion explosive matrices with various types of voids. These measurements serve the basis for predicting distances in water for sympathetic initiation for both spherical and linear charges. It is shown that the explosive-detonator system in combination has a far greater probability of initiation due to sympathetic shock pressure than either the explosive or the detonator alone. Various explosive matrices with air bubbles and glass microballoons have been examined and the differing sensitivities to shock pressure explained on the basis of these measurements. It is also concluded that explosives containing air bubbles instead of microballoons would be significantly more prone to sympathetic initiation.

Jan 1, 1992

By James G. Stuart, Tassilo N. Baur

We will discuss the kind of procedure that we use to predict the no-fire (for safety) and all-fire (for reliability) current levels for any given type electric detonator. The basic idea is to expose several detonators to different levels of electric current, so we can estimate the probability of firing as a function of current. We call this a statistical firing test. But what about the uncertainty in measuring the current? Suppose we are not quite sure what stimulus level we apply? This is the question that we will consider here. This relates to both safety and reliability. Surprisingly enough, we will find that some uncertainty in measuring the levels during our statistical firing test improves our long-term safety and reliability

Jan 1, 2019

By Cam Thomas, Steve Bernard

Various types of blasting instrumentation can be used in the field to analyze conditions before, during and after a blast, and to indicate what changes need to be made. When different types of measurements are combined together, the blaster can end up with useful data that can pinpoint the source or sources of problems and what changes have to be made. This paper outlines two case examples where blasting instrumentation was used to overcome problems in separate quarry operations. Extensive measurements with different systems led to significantly improved blasting results.

Jan 1, 2012

By Kush Patel, Gary Cavanough

Mining operations consume over 2.5 Billion Australian dollars’ worth of bulk explosives annually (Richardson, 2018). Despite the large volume of product used, current practices only conduct a cup density test of the product being used. Explosive products are made up of a number of components, each with an effect on the performance of the explosive. This paper presents methods currently available for the evaluation of bulk explosives and discusses the results of the evaluation of bulk explosives using each of the methods. Through the preliminary experimental analysis, wet chemistry and the Bulk Explosive Analyser were found as methods most suitable for the evaluation of bulk explosives. This paper also presents data obtained from the experimental comparison of the wet chemistry method and the Bulk Explosive Analyser. Through a total of 60 tests carried out on 10 different bulk explosive products the average error of each method was determined, the BEA presented an average error of 0.11%, whereas, the wet chemistry method presented an average error of 1.90%. This is a significant difference when considering the importance of formulation of explosives. Further investigation into the capabilities of the BEA are also presented in this paper.

By Dale S. Preece, Matthew A. Reisenmay, Avione Northcutt

The ability to simulate the explosive effects of land mines on military vehicles is a valuable capability in the defense community. The current competency levels of such simulations, however, are in need of improvement. Experiments have been conducted to measure the explosive induced impulse of a land mine on a steel plate placed above the explosive charge. The purpose of this paper is to report the findings of a variety of simulation tests conducted in order to correctly predict the empirical impulse data gathered in corresponding experiments. The computer hydrocode, AUTODYN v5.0.01 (Century Dynamics, 2003), is the simulation code used to simulate, and process the results. The experimental data has not been made available to allow computer analysts to exercise their codes on the problem without the temptation to tweak parameters in order to match computer code predictions with experimental results

Jan 1, 2005

By Steve Dillingham

Today, a typical blaster is likely to wear many hats, including, but not limited to, supervisor, risk manager, safety coordinator, explosives engineer, communicator, as well as professional decision maker. Simply put, a blaster in the new millennium is an all encompassing blast site manager. As you know, accidents on the blast site can range from blast crew injuries to blasting incidents resulting from vibration, flyrock, misfires, etc. Not surprising, the incidents can quite often be traced back to direct preventable human action on the blast site. They can, however, frequently be avoided, if responsibly identified early and managed properly by an efficient blast site manager. Your company cannot afford to simply employ blasters; good blast site managers are necessary to produce the safest results possible.

Jan 1, 2001

By Kameron Ray, Ruilin Yang

This paper compares the modeling results obtained by using a single seed waveform (SS) versus multiple seed waveforms (MS) as inputs to the Multiple Seed Waveform (MSW) blast vibration model. The field data for the comparison was collected at a coal mine. The results of the comparison showed that the MSW model yields more accurate predictions and significantly higher correlation to field measurement when using MS as input. When using a single seed waveform as input, different seed waves result in different predictions of PPV. In contrast, using the multiple seed waveforms as an input, more consistent results are obtained.

Jan 1, 2013

By Perry Sisk

In order to protect nearby structures during a blasting project, a peak particle velocity limit is often stipulated by a government agency or the owner of a particular structure. At the start of a blasting project, a preliminary estimate for the minimum scaled distance is often determined using a vibration prediction equation before any site-specific data have been obtained. Reasonably conservative assumptions are typically made for the unknown input variables in the vibration prediction equation until site-specific blasting data have been obtained and evaluated. Although this approach is prudent, it provides no assurance that the peak particle velocity values generated during the initial phase of the project will be below the specified limit.

Jan 1, 2013

By Tony Francelj, D. Scott Scovira, Remi Proulx

The Meikle Mine is a high-grade, underground gold mine that utilizes a primary and secondary stoping method with delayed backfill. The newly developed Rodeo Mine will start production using similar mining methods in late 2001. The combined production for the mines will be 4100 stpd of ore in 2002. Dilution of the secondary stopes resulting from blast induced overbreak of the backfill placed in the primary stopes was an issue identified as being a major contributor to the total mining cost at the Meikle Mine. To address the overbreak issue, a low-density, polystyrene enhanced bulk emulsion was developed and introduced to the mine. The density and energy of the emulsion was varied until an optimal level was reached. The use of a low-density bulk emulsion has greatly reduced the overbreak of the primary stope backfill when blasting the secondary stopes. Benefits to the mines include reduced secondary stope dilution, lowered total mining cost, and increased revenues.1

Jan 1, 2002

Dear All, I am looking for information about vibrations and effects on fish in pools. A tunnel blast is planned to be carried out as close as 300 meters to a freshwater fish growing plant. What is the vibration criteria for fishes in pools? Your comments will be highly appreciated.

Jan 1, 2012