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By A B. Jr Nunn, W C. Gould

Good community relations is a major concern at this central Virginia aggregate quarry. In this paper, the authors describe the use of a new electric millisecond delay initiation system that has reduced the average level of vibration by 27% since its use began in late 1984.

Jan 1, 1986

By Thomas Rupp, Michael Siegwart

The paper presents the vibration and sound emission measurement campaigns carried out in 2007 in preparation for the Ceneri-Basistunnel construction. We also present the vibration measurement campaign conducted during the construction of the Zimmerberg-Basistunnel. Both tunnels form an integral part of the Swiss Federal Railway Company Neue Eisenbahn Alpentransversale project (NEAT). This strategic project comprised the construction of several new tunnels. Its aim is the improvement of the existing infrastructure. The improved infrastructure will be able to accommodate a larger volume of railway traffic that is also crossing the Alps at higher speeds. The construction of the Ceneri-Basistunnel commenced in 2006. Both the Zimmerberg-Basistunnel and the Ceneri- Basistunnel are located underneath densely populated areas. Therefore, noise and vibration emissions have to be kept to a minimum and must not exceed applicable codes of practice. In order to identify the most appropriate blasting strategy for the yet to be constructed Ceneri-Basistunnel, blasting trials were conducted. The paper presents the findings of these trials and identifies ways to reduce both noise and vibration emissions from blasting. The construction of the first phase of the Zimmerberg-Basistunnel took place between 1999 and 2003. While the first phase is already in operation, the construction of the second phase has been postponed (commencement originally due in 2007). The Zimmerberg-Basistunnel connects the outskirts of Zürich with the city centre. As the tunnel site was not located close to the surface near populated grounds, no special measures were needed to reduce the noise emissions from blasting. However during the construction of the tunnel, the vibration emissions from blasting were monitored on more than 50 locations on the surface. The paper presents the analysis of some of the data. An emphasis is placed on the appropriate synopsis and presentation of data for documentation purposes.

Jan 1, 2009

By Raymond H. Green, Mitchell W. Green

The authors examined the application of precise millisecond delay electric blasting at a well-known Vermont quarry. The paper explains how the use of a new high-accuracy electric delay detonator has improved fragmentation, raised productivity 10%, simplified blast design, and increased the ability to predict results from blasting.

Jan 1, 1986

By George Pittman, Dan McCutchen

When an explosive manufacturer in the USA wants to put a new explosive formula or detonator design in the toughest proving ground in North American, it is Florida. Florida conditions have baffled many creditable blasting experts. This paper deals with some of the methods used to overcome these problems.

Jan 1, 1995

By Paul Worsey, Gillian Worsey

Description of Project:The basic blasting class underground lab at the Missouri S&T experimental mine in Rolla, o., shows the students how to drill, set up, load, and shoot a shot underground. In this case the shot was part of a new ramp to a second level.

Jan 1, 2014

By Thomas M. Keevin, Gregory L. Hempen

A study was conducted to measure underwater pressures associated with confined borehole shooting used to remove rock for The Kill Van Kull Deepening Project, U.S. Army Corps of Engineers, New York District. A major natural-resource-agency concern was the potential for fish mortality during explosive rock removal. Currently, fish mortality models are based on testing programs that exposed captured organisms to open-water blasts. Natural resource agencies, without in-house explosive engineering expertise, generally are not familiar with the physical properties of blasting underwater. Confined shots are most often used for demolition and rock removal underwater. Pressure amplitudes from confined blasts are significantly reduced as compared to open-water blasts that, are commonly used for fish testing The duties of natural resource agencies are made even more difficult by the lack of published data on pressures associated with confined blasting. As a result, explosive weights for confined shots mistakenly have been used to run mortality models that were developed using open-water blast pressure data. This study was conducted to collect pressure measurements during rock removal for the KVK deepening project and compare those data with computed peak pressures for open-water explosions.

Jan 1, 2005

By William Reisz

In our line of work,like many other professions, there may be times when circumstances or a series of events may arise, contributing toward unacceptable risk. When multiple parties are involved, there will almost inevitably be differences on how best to deal with these situations. Unless approached in an intelligent and these differences may often have the potential for costly and unexpected results.

Jan 1, 2014

By Sharon K. Reamer, Klaus G. Hinzen, Brian W. Stump

"This study investigates seismic wave propagation from two production shots in a limestone quarry. Our motivation is to investigate the efficiency of two superpositioning techniques. The production shots consisted of an 18 and 20 hole explosive array detonated in a single row with constant delay times of 32 and 20 ms, respectively. A single shot was fired on a neighboring part of the quarry bench. The experiments were instrumented with 20 three component seismometers (35-120 m range). The computer-controlled electronic firing system resulted in firing time deviations of less than 1.4% of desired fired times. Linear superpositioning with the observed single shot data produces seismograms which adequately reproduce temporal effects of the multiple explosions; however, spatial effects due to the extended source length (68-76 m) are not modeled with this method. Linear superpositioning with individual half-space Green's functions for each explosion in thearray convolved with a calculated Mueller-Murphy source produces seismograms which match the time duration of the observed production shot seismograms and differ in absolute peak amplitude by less than a factor of three. Parameter estimation for the source is taken from chemical explosion study results. The single source model differs in amplitude from the observed single source seismograms by a factor of 2.3."

Jan 1, 1991

By Emmett J. Ientilucci, Martin Held, Xuesong Liu

Mining is crucial for advancing technology and science by providing essential resources and materials. Quarry blasting, a necessary process in mining, releases these resources and chemicals, driving research and engineering improvements. However, NOx (nitrogen oxides) is an undesired contaminant produced during quarry blasts, posing a significant negative impact on mining activities. Therefore, detecting and quantifying NOx emissions is essential for designing effective blasts, analyzing their dynamics, and reducing contaminant production. Image processing and machine learning, including deep learning methods, have been applied to solve smoke plume detection and segmentation tasks. Most research has focused on smoke from campfires or forest fires, which are important for early fire and smoke detection. However, there is limited research on quarry blast smoke using machine learning methods, which presents challenges for recognizing the smoke plume from complex background scenarios and objects, including collapsed rocks, scattered soil dust and dirt, and the dynamic movement of the scene due to blast vibrations. Detecting NOx within the smoke plumes is further challenging because NOx must be distinguished from the overall smoke plume, as they share many common spatial features. To resolve this issue, we propose an ensemble method for NOx detection that combines smoke plume segmentation with NOx fume detection. First, we apply a smoke plume segmentation model to identify the smoke plume regions. Then, we use these masked-out smoke plume regions to detect NOx based on its unique color features. The first stage of the ensemble method helps block out complicated confusers in the background, such as reddish and brownish dirt. Next, we specifically design a color classifier for NOx to further improve its sensitivity. We evaluate the overall video-wise performance using accuracy, false alarm, and miss rates based on sampled image frames from videos. Additionally, we assess the mean Intersection over Union (mIoU) for smoke plume segmentation and the mean Average Precision (mAP) for image-wise performance from an algorithmic perspective. In summary, this paper represents the first attempt to apply machine learning approaches to NOx detection in a memory-efficient and time-efficient manner.

Jan 21, 2025

By L. M. Lopez, J. A. Sanchidrian

This work investigates the performance of some of the measurement techniques used in vibrations from blasting monitoring. Two tri-axial geophones with cases of different size, shape and mass were tested in a shaker table. The geophone cases were mounted in three different ways on a granite slab fixed to the plate of the shaker: freely placed, sandbagged, and anchored. A known horizontal periodic motion of constant amplitude, and frequency from 16 to 200 Hz, was applied to the slab. Two amplitude levels of 5 and 20 mm/s (0.2 and 0.79 in/s) were applied when the sensors were sandbagged or anchored and only 5 mm/s when no holding force was applied. The transmissibility of vibrations from the rock to the longitudinal geophone as function of the frequency (i.e. ratio of response of the geophone to the slab motion) has been obtained for each measuring condition tested. The transmissibility is considered a composition of the transmissibility of the rock-to-sensor coupling and the transmissibility of the sensor’s mechanics and electronics. The transmissibility of the coupling is obtained normalizing the total transmissibility with the transmissibility of the seismographs, obtained by a suitable test to which a coupling transmissibility of 1 is assigned. Geophone-to-rock coupling is a resonant phenomenon that may alter the amplitude of the measured waveforms by a factor of 1.2 to less than 0.6. The most accurate and precise measurements are obtained with geophones anchored to rock. On the contrary, freely placed or sandbagged sensors are non-predictable planting conditions that lead to high amplification or damping in most of the frequency band analyzed. It is also shown that existing acceleration criteria to select coupling methods do not necessary lead to good quality (accurate and precise) vibration data.

Jan 1, 2014

By He Guangyi, Han Zhilong

This paper introduces the new technology of deep-hole blasting with water-soil mixed stemming to exposed stonework. Nine aspects of advantages are drawn in the paper based on tests of different types of charge and stemming under the conditions of different geology, height of bench and diameter of drill.

Jan 1, 1998

By Walter Voglauer, Elisabeth Zechmeister

Description of Project: The four photos show a chimney blasting operation in Vienna’s district of Floridsdorf on May 4 2011. The blasting was done with two types of charges. An internal charge provided a force of blast which resulted in 135 single electrical blasting caps initiated detonations on the basic ensured the straight collapse of the chimney. The preparation work was done by reserve force military engineers. The series of photos were shot by Elisabeth Zechmeister. She works in the Austrian DOD but not as a professional photographer; much more she did all activities in her spare time.

Jan 1, 2013

By Yessica Idrogo

"Undoubtedly mining is currently the activity that brings a great development for all countries involvedin this industry, which means that to develop mining requires adequate explosive mixtures. The following work about AL/AN/FO is presented, knowing that this is a dry blasting agent, which iscomposed by ammonium nitrate, petroleum diesel N°2 and aluminum (AN, FO, AL). It is known that this dry blasting agent AL/AN/FO was invented by A. Baver Ph. D. in Marcona Mining Company, 12/12/1968, where in that investigation also worked Carlos Agreda Ph.D. as assistant of the mentioned inventor."

Jan 1, 2017

By William Reisz

The explosives and blasting industry has a commendable safety and security record, especially over the last several decades. This is due in large part to our newer technologies, better training and education, engineering practices, corporate initiatives, our professional organizations, and whether we like to admit it or not - our regulatory agencies.

Jan 1, 2012

By Joshua Hoffman, Braden Lusk, Perry Kyle

With the advent of any new technology comes the necessity of fully understanding the mechanics of that technology. The Shock Tunnel is one such technology that provides a cost effective means of simulating large-scale explosions while requiring a fraction of the explosive and space. Although the technique is known and practiced, the dynamics and mechanics of this technology has yet to be fully understood. A relationship between the energy potential of a given explosive and the energy realized at a set of distances was determined. This data was then compared to the energies realized from the same explosive when utilized in conjunction with a shock tunnel. A relationship between potential and realized energy outputs from explosive based shock tunnels exists and the understanding of this relationship would allow all for predictions to be made to forecast a specific amount of explosive required to produce a desired energy output. This energy output should then be relatable to peak pressures produced via the shock tunnel. Two shock tunnels are currently accessible for this study, the first under the direction of the University of Kentucky, and a second under the direction of the Missouri University of Science and Technology. The two shock tunnels differ in dimensions but share common construction materials. Energy realized from a shock tunnel is hypothesized to be a function of the shock tunnel’s dimensions. This study explores how different geometries affect the shock tunnel’s performance; this exploration is broken down into three phases. Phase 1: Open arena testing in which theoretical energies produced by the detonation of small (<1.0 kg) charges are compared to actual experimental values. Phase 2: Shock Tunnel testing in which realized energies are experimentally recorded for the UK shock tunnel. Phase 3: Analysis of the data to lay down the ground work for producing a pressure-forecasting tool given shock tunnel dimensions and explosive characteristics with the possible detection of avenues for optimization of shock tunnels.

Jan 1, 2009

By Robert Jacob Cefalo, Rio Tinto Kennecott

At the end of 2016, the Mine started a new ore phase in the section of the pit located on the East Wall. The East Wall geological structures required controlled blasting for peak particle velocity (PPV) frequency vibrations to protect the wall. Frequency controlled blasting using linear seed wave superposition modeling was required and implemented to reduce the far-field affects to the wall. This paper covers the work done by the drill and blast engineering group, controls used to protect the mine infrastructure, and the continuation of work-to-date of frequency controlled blasting for wall stability. The narrow width of the layback required the combination of hole sizes to blast large diameter production patterns with smaller diameter trim patterns in the same blast. A single blast had to use different burden & spacing and hole diameters and required the use of different timings throughout the pattern. Electronic detonators were required to limit blast vibrations and accommodate the specific timings needed to reduce low frequencies. The geotechnical group with the help of geotechnical radars worked with the drill and blast group on creating a tracking and reporting of blast performance. The radar readings informed the drill and blast engineers of the performance of the blast as it related to the long term performance of the highwall

Jan 1, 2019

By Paul N. Worsey

Disturbed zones of rock have been measured for blasted highway rock cuttings by Matheson and Swindells of the Transport and Road Research Laboratory (TRRL) of Great Britain. These zones have been shown to be directly attributable to the blasting process and accordingly vary in depth depending on blasting technique. Perimeter blasting such as smoothwalling and pre-splitting has been shown to be effective in reducing the depth of disturbed rock. Although extensive work has been carried out on surface excavations for medium diameter (l00mm) blast holes, none has been undertaken for underground excavations.

Jan 1, 1985

By Dr. Zach Agioutantis, Elliott Morgan

The explosives, mining, and heavy civil industries consistently battle the uncertainty that is associated with working with a heterogenous medium like rock in blasting. This has led to studies to increase fundamental understanding of material response under dynamic loading that is associated with blasting. This study looks at the dynamic strain associated with blasting the lab Split-Hopkinson Pressure Bar (SHPB) testing while also building off of previous studies with the goal of better understanding the dynamic forces that are enacted on a geologic body during a blast loading event. This is required in order to advance geologic blast response modeling. This is achieved through analyzing the stress and strain values for each specimen that are calculated from strain data collected with a SHPB. Based on this data, the dynamic material response characteristics are able to be determined. Tests were conducted on five Berea Sandstone specimens with a rough length to diameter ratio (L/D) of 1.0. The strain data from these tests were then used to create stress strain curves as well as charts depicting failure stress to both strain rate and failure particle velocities. The tests conducted returned similar results to previous tests results on Berea Sandstone while also showing a correlation between strain rate at failure and failure particle velocities. While further research is needed, there is evidence that SHPB test data could be used in conjunction with the MBF model. The MBF model states that the peak particle velocity (PPV) of blast vibrations can be correlated with deformation (strain) at a given point. With a further understanding of dynamic material response correlated to PPV measurements, further refinement could allow for better prediction of blast performance.

Jan 21, 2025

By P A. Lang, J G. Ayotte, R W. Humphries

Atomic Energy of Canada Limited (AECL) has the responsibility for research, and development of technologies, for the safe and permanent disposal of Canada's nuclear fuel wastes. As part of this comprehensive program, AECL is constructing an Underground Research Laboratory (URL) near Lac du Bonnet, Manitoba, to evaluate aspects of the concept of waste disposal deep in stable geological formations. No nuclear wastes will be used in the URL program.

Jan 1, 1986

By Isaac E. "Chip" Harris

A general understanding is given to how and where blast hole drills are used and what recent developments have taken place with small and large diameter drill hole machines. Indications are that new developments with high penetration rates and large diameter holes are not necessarily the answer to increased production in the field.

Jan 1, 1979