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By Travis Davidsavor, David Provost

A segment of high-pressure steel petroleum pipeline needed to be replaced on a hillside and beneath a waterway within an existing right-of-way containing multiple petroleum pipelines. The pipeline replacement required excavation of sedimentary rock to allow placement of the new pipe. As a result of an existing right-of-way limitation, steep slopes, and hard rock, blasting would be required as close as 7.8 meters (25 feet) from two operating pipelines. Existing pipeline company standards would have effectively precluded the construction of the replacement pipe by blasting rock. To facilitate the required construction and evaluate actual pipe stress during blasting to ensure pipeline integrity, a comprehensive evaluation methodology was developed by a team of pipeline, mechanical, geotechnical, instrumentation, and blasting engineers. A total of 60 strain gages were affixed to the steel pipe and seismographs were buried at the surface near the blasting area. Test blasting allowed pipe stresses with corresponding ground motion to be monitored. A conservative analysis approach evaluated individual peak strains and revealed that only small pipeline strains, and therefore stresses, were induced in the pipeline as a result of blasting. This evaluation allowed specific procedures to be developed to inform the blasting operation of maximum explosive loading and minimum charge distances. Additionally, this effort provided the pipeline operator with appropriate pipeline operating pressures during blasting activities to limit total stresses in the pipeline to be below allowable stresses imposed by code, regulators, and company operational limitations. Recommendations were developed to measure the blast generated ground vibrations with seismographs buried at the depth of the pipe, near the pipe, and limit the ground vibrations from blasting to 150 mm/s (6 in/s). If ground vibration intensities of 120 mm/s (4 in/s) or more were observed, additional engineering review is recommended. Finally, all blasting would be suspended and all activities reviewed at peak ground vibration intensities of 230 mm/s (9 in/s). The evaluation effort resulted in effective and efficient construction of the pipeline replacement and allowed the pipeline operator to better understand blasting induced stresses on their assets.

By Wayne A. Charlie

An experimental test program being conducted at Colorado State University and involves the study of the behavior of water saturated sands under shock and explosive loadings. The study is being conducted to evaluate potential blast induced changes in dynamic soil properties, soil shear strength loss (liquefaction) and densification of water saturated sands under single and multishock loadings. This paper presents testing and measurement objectives, and the equipment and instrumentation developed to load, measure, record and analyze the transient and long term soil behavior. The laboratory shock facility is capable of generating multi-shock pulses with milli-second rise time, peak stress amplitudes of up to 35,000 KPa (5000 psi), peak particle velocity of 5000 cm/set and peak acceleration of 10,000 g. The field explosive facility subjects saturated soil to controlled explosive loadings. Of major interest is the soil strain and water pressure, both during and after the passage of the stress wave, as a function of peak particle velocity, peak strain, loading rate, soil density, initial confining stress and the number of loadings. Based on data obtained to date, soil densification is due to consolidation following liquefaction.

Jan 1, 1991

I attended a funeral in West Monroe, Louisiana, for one of the best powder peddlers I’ve ever known. He started work in 1948 for Dixie Dynamite, a seismograph explosive distributor. His first job was as a truck driver, then magazine keeper and then sales re p re s e n t a t i v e . When Dixie Dynamite quit, he acted as an explosives sales agent for sometime before moving on to Kansas to be a sales rep for a distributor there. We called him the “ragin cajun” long before James Carville came on the national scene messing up things. While he was born in G e o rgia, he was a Cajun at heart. I don’t believe the old saying, “Build a better mousetrap and the world will beat a path to your door.” To me, the best products in the world need to be sold. Two examples of this are the Beta system for TV and the Apple Macintosh computers. Beta is the best system but VHS took over because the Beta people fell down on the selling job. Windows 98 is Macintosh ‘86 but again the engineers were not salesmen. Marion “Johnny” Johnson who was buried only about a half mile from his first magazine site proved that good selling is good citizenship. He could have sold any firstclass product, for he wouldn’t tolerate inferior items, and made a successful career of it, but he chose dynamite and the industry benefited from his talents.

Jan 1, 2004

By Ph. D. Favreau, Favreau Patrice B. Eng, R. F.

Geology is important in mining by helping to identify the rocks which contain sufficient valuable ore to justify their excavation. Geologists give a geological name to each rock type, so geology is a player in blasting; when a blaster has successfully blasted rock of a given geological name at a former site, and he later has to blast rock at another site whose rock has the same geological name, then his first trial often is the same method as he used at the former site, since the geological name of the rock is the same

Jan 1, 2019

By Gary Kahn

In this document the VODR is discussed from a technical point of view and is intended to give the reader a feel for the design of the instrument, its technical specifications, and its limitations. It is not intended as a tutorial on the use of the instrument in the field.

Jan 1, 1989

By David Scutt, David Noon

Blast crews are exposed to a number of major hazards including explosives and chemicals, ground conditions, machinery, unique work environments and specific blasting hazards such as fly rock and misfires. Unfortunately, injuries caused by sudden and/or unexpected movement of ground are continuing to occur. Blast crews are not equipped with the knowledge or tools to understand whether a high wall that they are planning to work under is safe.

Jan 1, 2011

By Paul Worsey, Delbert Da, Eric Achelpohl

The University of Missouri-Rolla is currently researching the concept of using glass microspheres in explosives as taggants as part of a 3-year technical project funded by the Bureau of Alcohol, Tobacco, and Firearms. These taggants are intended to provide two functions, first explosive detection and second post explosive event identification. The key priority is being able to detect explosives used in terrorist acts prior to detonation. The research on the use of microspheres includes the development of indicator taggants for the purpose of revealing the presence of hidden explosives, by either emitting radiation when bombarded with neutrons or emitting selective vapors, such as DMNB which may be readily “sniffed”. Of secondary importance, after an illegal explosion, the tags serve to identify the lot number, etc of the explosive. This information is to aid in the tracking, arrest, conviction and imprisonment of the perpetrators.

Jan 1, 2001

By Edward Barrody

There are wide variations in the values of heats of explosion and detonation as reported in literature. These values are not “stand-alone” or sole properties of the explosives. Specifications of the conditions under which they were determined are necessary to characterize these values. This paper proposes that these values are dependent on their oxygen content and the surroundings their products “work against” upon expansion. Also, the heats of explosion and detonation values can have the same values, but different products, showing that the products can take “independent paths” but have the same values.

Jan 1, 2003

By Jason Baird, Joshua Hoffman, Phillip Mulligan

The purpose of this report is to address the method of reducing the overall explosive weight of Explosively Formed Projectiles (EFPs) while still achieving satisfactory performance. This reduction is crucial in order to comply with outdoor explosives testing standards for Missouri University of Science and Technology’s (Missouri S&T’s) Experimental Mine. Initial EFP design testing exceeded given limitations, making reliable data difficult to ascertain. EFPs must be tested outdoors to allow for specific information recordings which aid in defending against them.

Jan 1, 2010

By Zvonimir Ester

The course of motorway tunnel under construction was set only 2 m away from the main motorway. The thickness of the tunnel overburden rock was 9 m. During the tunnel construction the traffic on the motorway was not supposed to be interrupted. The tunneling was carried out by NATM with classical drilling of blastholes and by blasting.

Jan 1, 1998

By Sandra Penttinen

There are several ways to get a positive reaction from neighbors to blasting projects. When you need to enter structures to conduct a pre-blast inspection, the impression you make on the structure owner must be positive from the very start. Public relations with neighbors is the key. The purpose of all communications with persons residing near planned blasting operations is to educate structure owners as to what will take place during the blasting operations, to explain that safe blasting practices will be followed and vibration and airblast limits will be imposed to protect surrounding structures from damage. Once access into the structure is obtained, the structure owner can be shown, by careful documentation, all existing cracks and defects in the structure prior to blasting and construction. The objective of your visit and all communications is get your foot into the door and win the confidence of the structure owner so that he or she understands blasting will not compromise the structure.

Jan 1, 2006

By Kush Patel

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.

Feb 1, 2020

By Wilfrid Comeau

The RICHTER scale is used in classifying earthquake severity. It is an energy scale giving the estimated energy liberated at the source of the earthquake. Earthquake damage on the earth’s surface, for example at the epicenter - spot on the earth’s surface directly above the earthquake, for a given RICHTER number can vary. This depends on the depth of the earthquake focus. Deeper earthquakes will generally cause a lower level of damage at the epicenter but the damage will be spread over a greater area. As mentioned by Randy Wheeler on Blastserve, each successive RICHTER number represents about a 30-fold increase in energy. This scale is open at both ends with “0” RICHTER equal to about 104 Joules. The lowest level detected by sensitive instruments is about 2 on the RICHTER scale or about 107 Joules. The highest-level earthquake detected at 8.9 RICHTER represents a release of about 3 x 101 7 Joules.

Jan 1, 2003

By Jack Eloranta

To improve control of blasting, tests were performed to assess non-electric cap accuracy. Simultaneous testing using a Velocity of Detonation Recorder (VODR), Red Lake Lo-Cam and an Instantel DS-677 blast monitor was done. Favorable comparisons were found in the three records . This testing confirmed the accuracy of an inexpensive and expedient cap testing procedure.

Jan 1, 1992

By Steve Kane

Lightning is a very real problem in the surface mining industry. Today, as adverse market conditions continue to influence the surface coal industry, it has become necessary that all functions of the surface mining process become as efficient as possible. High production with reduced manpower is the winning combination of staying competitive in the market place. We at AMAX Coal are committed to staying in the coal business, but we have always been committed to providing a safe work environment for our people and will continue to do so in the future. Approximately two years ago, our Midwest mines installed state of the art lightning detection and warning systems at our mines. This paper will cover its application at Delta Mine; the benefits and problems encountered, and the impact this system has had on Delta Mine.

Jan 1, 1992

By Jeff Hammer, John McGregor

"The Twin Tunnels, originally constructed in 1964, have become a major choking point for trafficheading up to and returning from the Colorado high country along the I-70 corridor. To increase traffic flow, the Colorado Department of Transportation undertook the first widening of the East Bound Tunnel in 2013. After the successful completion of that project, CDOT began the widening of the West Bound Tunnel in 2014. Both projects had a limited schedule for tunnel construction of just nine months. The innovative blasting and demolition of the existing tunnel lining was a crucial component to the success of both projects. During the construction of the West Bound project in 2014 a large amount of surface bench blasting using conventional methods ran concurrently to the West Bound tunnel excavation to allow for enough room for the new tunnel portals."

Jan 1, 2016

By Jerry Wallace

Construction of a new grammar school required blasting within three meters of the existing school. Due to changes not anticipated at time of bid opening, blasting had to take place while approximately 200 children were in attendance inside the building. Blasting with children in such close proximity forced the blaster to review and revise a systematic approach to construction blasting and make changes to previous Rules of Thumb guidelines. The revised rules of thumb place Blaster-in-Charge at the top of the List. Other changes specific to the project included putting in place a blasting safety plan that included communicating the serious job hazards to teachers and students. The plan included stringent lockdown guidelines establishing school procedures for accounting for each student prior to the countdown-to-blast being implemented. Emergency communications channels were kept open so that any scheduled blast could be aborted at the last instance.

Jan 1, 2001

By Lon Santis, Michael Swisdak, David Leidel, John Tatom

The Institute of Makers of Explosives (IME) and A-P-T Research, Inc (APT) have developed and released a quantitative risk management tool, IMESAFR (IME Safety Analysis For Risk), for the commercial explosives industry. Consequence algorithms in IMESAFR are considered state-of-the-art. Generally, they mirror those in SAFER (US Department of Defense Explosives Safety Board quantitative risk management software). The science behind the software has now been assessed for its maturity. Results have identified areas where additional test consequence data could improve predictions. To address these areas, full-scale testing programs to provide the needed data have been formulated. Proposed testing efforts include work to: (1) improve characterization of explosive articles now absent from SAFER, and (2) refine modeling of the Potential Explosion Site (PES) types, particularly small metal structures, also not found in SAFER. Goals of each program as well as requirements for conducting the tests have been established. Testing results are to be used to improve the algorithms and to further the state-of-the-art in risk-based explosives safety.

Jan 1, 2012

By Don Bachman, Larry Heywood

Artificial release of snow avalanches, through the use of explosives, is a necessary component of safety planning and operations for ski areas throughout the Western United States, as well as in other alpine regions of the world. Climatic, meteorological and terrain factors leading to the development of avalanche conditions, in addition to release mechanisms and magnitude of the avalanche problem to ski areas will be discussed.

Jan 1, 1999

By D. Rudenko, C. T. Aimone-Martin, J. K. Ratliff, I. G. Wong, J. Aiken, R. E. Burnham, T. A. Davidsavor

A small quarry blast was conducted with a maximum of 90 pounds per delay and shortly afterwards, area residents sensed ground motion and building shaking indicative of an earthquake. In addition, seismometers up to 500 miles (800 km) away recorded a magnitude 2.8 earthquake located in the area. Positioned in a seismically inactive area, southern Minnesota is not known for earthquakes. The earthquake was originally described by the USGS to be a surface blast at the quarry. Analysis showed that the earthquake occurred shortly (approximately seven seconds) after the quarry blast some distance away and well below the surface. This paper describes the evaluation of the “seismic events” including the blast, the following earthquake, initial governmental response, and provides the framework for assessing the relationship between the blast and the earthquake. The paper also discusses management of large volume claims from a complex event and presents a claims management strategy with best practices.

Feb 6, 2023