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By Carl E. Jones

This presentation discusses the properties of the two-component explosive, KinePak, and how it is used by the utility industry.

Jan 1, 1978

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 Calvin Konya, Steven S. Spagna, Ed Smith

During Summer 2001, the U.S Army Corps of Engineers awarded a contract to the construction firm of Bush and Burchett of Allen, Kentucky, for the purpose of developing a 13 acre redevelopment site by removing approximately 2.5 million cubic yards of rock (fig. 1). The Redevelopment Site will be the future home for a large portion of the City of Grundy, Virginia. Additional work items include the construction and relocation of 3,000 feet of the Norfolk Southern railroad bed, the placement of 95,000 cubic yards of fill and the placement of 16,000 cubic yards of stone slope protection along the Levisa Fork River. Bush and Burchett received a notice to proceed with construction in July 2001. Currently, the contract is near completion. Current activities include: hauling of material from the Redevelopment Site to the disposal area; placing fill material on the Redevelopment Site, and placing Stone Slope Protection (SSP) along the Levisa Fork river. Approximately one year into the construction highly weathered rock, degraded to near soil- like condition, was encountered in the upstream portion of the excavation. Over one-third of the original cut slope was adjusted and the blasting specifications had to be amended to accommodate for the material that was encountered in this area.

Jan 1, 2005

By Brian W. Stump, David P. Anderson

Identification of seismic events detected under a Comprehensive Test Ban Treaty requires a clear physical understanding of the different types of seismic sources including mining explosions, rock bursts, mine collapse and small, shallow earthquakes. Constraint of the operative physical processes in the source region and linkage to the generation of seismic waveforms with particular emphasis on regional seismograms is needed. In order to properly address the multi-dimensional aspect of data sets designed to constrain these sources, we are investigating a number of modern visualization tools that have only recently become available with new, highspeed graphical computers that can utilize relatively large data sets. The results of this study will provide a basis for identifying important physical processes in the source region that contribute to regional seismograms.

Jan 1, 1995

By Monica Stuckert

Field studies were made at an Appalachia coal stripping operation to evaluate the differences in cost and performance between blast casting with pre-split dewatering versus conventional coal overburden blasting.

Jan 1, 1985

By Ralph King

Blasting has been completed when the lawyer calls to say that a landowner has filed a suit alleging damages to the roof of his home. Mitigation talks fail to produce an adequate resolution and the case goes to court. The blaster has pictures of the area made after the blasting was done showing the good condition of the roof. However the judge fails to allow the photographs to be entered as evidence and the homeowner wins the case.

Jan 1, 2008

By James McGough, Lawrence Mirabelli, Ran Tamir

The paper will demonstrate how automated fragmentation photo analysis is being used at the Lafarge North America, Ravena NY quarry as part of an ongoing drill, blast and primary crushing continuous improvement process. Using on-line fragmentation photo analysis systems at both the primary crusher feed point and crusher discharge belt, data is collected to: benchmark the drill/blast process; monitor the work being done by the primary crusher; measure gradation changes in the crusher feed resulting from changes in drill/blast and measure the subsequent changes in further size reduction done by the primary crusher.

Jan 1, 2012

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 Joshua Micah Hoffman

While it is easy to state that meaningful involvement of the community can play a critical role for a successful blasting operation, following through with this involvement is not an easy task. Structured Public Involvement (SPI) is a developed protocol for involving communities in project planning decisions and could be readily applied to the blasting industry. SPI was developed for the purpose of collecting quality public input about public transportation projects. The purpose of SPI is to bring about stakeholder satisfaction with potential projects by allowing controlled input from the stakeholders. It was designed and intended for democratic societies that have come to expect a voice in public projects. While blasting operations are not always in the domain of public projects, the fundamental process outlined by SPI can be useful for collecting feedback from the immediate public around blasting operations.

Jan 1, 2014

By Wesley L. Bender, James E. Murray

Pre-blast surveys are often conducted solely to document existing structural conditions and uncover potential problem areas. This paper presents a case history where the pre-blast survey was also used as a vehicle to initiate a public relations program with the occupants of a large apartment complex adjacent to a major excavation site. The public relations program, in conjunction with good blasting practices, succeeded in keeping complaints to a minimum. The presentation includes an overview of the project, details of the public relations program, some of the blasting methods that were utilized and a recap of the complaints received.

Jan 1, 1988

By Billy Rosseau, Mike Cammack, Richard O’Meara, Gustavo Azpilcueta

During the summer of 2014, the U.S. Army Corps of Engineers (USACE) sought proposals to vastly improve and expand the small boat harbor in Valdez, Alaska. It would be a multi-year project, and construction was scheduled to begin in the spring of 2015. One aspect of the project was the construction of a 3,100 feet (1000 m) rubble-mound breakwater to protect a mooring basin. An estimated 208,500 tons (190,000 t) of rock, ranging in size from 160 to 3500 lbs (73 – 1600 kg), were needed to build the breakwater. The Glacier Point Quarry was selected as the rock source due to its proximity to the project and the quality of the rock meeting all of the USACE rock standards.

Jan 1, 2017

By Ruilin Yang

Based on large amounts of field data, this paper evaluates the validity of the above equations. During the evaluation, the different selections of the frequency in the equations were examined with field data. It is found that when they are used to estimate the vector sum values the above equations could result in large deviations from the values obtained directly from the field measurements or the waveform integration. The simple equations may be used to make rough estimations for single components of blast vibration provided that appropriate safety factors are taken into account. For single component vibration, the principal frequency (from ‘zero-crossing’) seems more effective to describe the blast vibration than the dominant frequency (fron FFT) for vibration peak value estimation using the simple equations.

Jan 1, 2012

By Orica

Unlicking the Possibilities ISEE Digital Detonator Workshop New Orleans, LA Wednesday, February 4, 2004

Jan 1, 2004

By Rob Farnfield, Yuill Gavin

The rock blasting industry continues to be under pressure to reduce the level of vibration induced by the use of explosives. In recent years much research and development has been directed to minimizing vibration levels by controlling the delay period between blast holes. The most commonly applied technique is known as Linear Superposition. This technique takes the vibration produced from a single-hole test shot and simulates the vibration that would be produced from a full-scale production blast. The simulation can be run with various delay periods and the optimum delay chosen. The success of the Linear Superposition technique depends to a great extent on having accurate delay detonators and on the single-hole test shot reliably indicating the vibration signal produced from each hole in a production blast. A quarry-based case study is given illustrating how these assumptions are not always valid. In this case the use of electronic detonators has controlled frequency but not vibration level. The paper goes on to describe a series of single-hole test shots in an U.K. limestone quarry. The vibration 2 signals recorded are examined in terms of variations in free-face provision, blast geometry, explosive properties, etc.

Jan 1, 2001

By Dworzak, Andrzej Biessikirski, Jozef Pyra

During the detonation process 20-30% of the energy is being consumed only on the quarrying pro-cess. The remaining amount of the energy generates harmful effects such as: shock wave, acoustic wave, fly rocks and ground vibrations. The ground vibrations effect is the most dangerous especially to structures which are situated nearby an open pit mine.

Jan 1, 2015

By Neal Lee

Reduced relief horizontally means an increase in energy expended vertically into the rock surrounding the stemming column, and potentially through the stemming column. The vast majority of holes in any surface blasting operation are afforded two horizontal relief faces at the moment of firing, whether by existing relief faces in front of and to one side, or previously blasted hole(s) in front of and to one side of the holes in question. When the energy expended in any hole on the blast pattern has less than two Horizontal Relief Planes or faces (referred to moving forward here as “HRPs”) available to it at the moment of firing, a higher percentage of the available energy is directed vertically. In the analysis of recorded videos by the author, one will note the fact that stemming ejection/flyrock is observed to a much greater degree from the center of almost all patterns when they are timed to “pull out of the middle” (“box cut" timed patterns). This is because the first hole to fire in each row has only one Horizontal Relief Plane, which significantly decreases horizontal avenue for energy release for these holes. This of course results in an increase in the amount of energy expended vertically. This paper proposes a novel methodology to modify the stemming to better use the explosives energy of each hole, while controlling side effects such as flyrock and airblast.

Feb 6, 2023

By Kevin Phelps, Jason Baird

When dealing with high velocity projectiles, the ability for researchers to accurately and precisely measure the velocity of the projectile is of great value. This report will analyze three different methods of recording high velocity projectiles for: their ability to record velocity data, pros and cons for each method, and any possible bias or limitations that would result. Method 1 uses a Phantom V10 high-speed video camera and a velocity reference screen to record the projectile’s path and proprietary Phantom software to analyze the data and determine velocity. Method 2 utilizes two break screens. This method, consisting of strung copper wire as the break material, is one that has been used in the past by Missouri University of Science and Technology (MS&T) researchers in assisting in finding velocities of high-speed projectiles. Method 3 is a pair of make screens, similar to Method 2 in that two screens were used for each test but relies on a projectile making a circuit between two sheets of metal separated by an insulation layer, to find a velocity. All three methods will be used simultaneously in each shot to rule out any projectile differences in subsequent shots. Projectiles of three different relative velocities, low, medium, and high, will be fired and analyzed to determine strengths and weaknesses of each method.

Jan 1, 2014

The VoD of non-ideal explosives depends on the charge diameter and the thickness, strength and sound velocity of the confiner. VoD measurements are made to evaluate explosives for development, quality control and prediction of field performance. In testing, the container is part of the explosive system and affects the measured VoD. Pipe testing in cardboard tubes delivers the best guide to unconfined critical diameter and minimum VoD range, but the thickness of the pipes affects the result close to critical diameter, even in emulsions. PVC pipes are not good for unconfined test work because they provide relatively strong confinement. Care must be taken to select pipes with constant relative pipe area across the range of diameters. Where pipes are used to evaluate the effect of confinement, the ratio of the wall thickness relative to the thickness of the detonation driving zone in the explosive needs to exceed 0.5 to create full confinement and the ratio of the detonation velocity to the confiner wave speed must be considered. Estimates for critical thicknesses are provided from Non-Ideal detonation models. The relationship between confinement modulus and VoD is discussed and indexes are suggested for quantifying the explosive performance.

Jan 1, 2007

By Catherine T. Aimone-Martin, Brent Meins

Blast vibration monitoring for buried pipelines is typically conducted at the ground surface with a shallowly buried geophone. In many jurisdictions across the U.S., blast-related vibration limits set for pipelines are dictated by surface measurements and do not consider the significant reduction of PPV amplitudes acting on the pipe at depth. This study involved a vertical array of geophones deployed in drilled holes at two blasting sites of the Loop 202 South Mountain Freeway construction project in Phoenix, Arizona. City of Phoenix pipeline engineers were concerned that blasting would damage an aged 48-inch (122 cm) prestressed concrete cylinder pipe (PCCP) that serviced water for South Phoenix

Jan 1, 2019

By Bengt Niklasson

"A test stope at the Luossavaara Research Mine in Kiruna, Sweden,was divided into four different modules in which various hole patterns and explosives were tested in order to evaluate:1. The optimum combination of explosive and hole pattern2. The resulting fragmentation3. The damage to the surrounding rock4. The application techniques of the VCR mining method"

Jan 1, 1985