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By P D. "Takis" Katsabanis

The phenomenon of sympathetic detonations in blastholes is investigated by comparing experimental observations and numerical modelling results. Numerical modelling using the TDL computer code and Forest Fire decomposition rates for commercial explosives has shown the importance of blasthole diameter, impedance of the stemming and host rock. Comparison with experimental observations has also shown that sympathetic detonations cannot always be treated as shock to detonation transition. Examination of previous results which have been obtained from calibrated low amplitude shock experiments reveal that there is an ignition threshold prior to the detonation threshold. The difference between the two thresholds is more pronounced in the case of air bubble sensitized products. The ignition threshold can be very important under the confinement provided by the blasthole and the conditions of application. It also correlates well with the pressures expected at the gap distances of interest in the practical application. It is suggested that critical energies are used as the criterion for cross initiation in blastholes. Practical suggestions based on the numerical calculations and experiments based on these calculations are also given and discussed.

Jan 1, 1991

By Harry L. Siebert

A major Arizona highway project is jeopardizing site safety and security because of the lane rental policy. One million cubic yards of rock must be fragmented to provide two additional lanes parallel to the existing roadway. Traffic is stopped during blasting operations.

Jan 1, 1997

By Ken Cross

This paper aims to demonstrate that explosives organizations and workers have a legal, moral and financial duty to be able to demonstrate their competence when required, and how that may be achieved at any level from explosives storekeeper to senior explosives engineer on a major project. The concept of competence is outlined, as are the benefits to members of staff, management and the organization, particularly in a regulatory regime that includes competence management as a key performance indicator.

Jan 1, 2013

By Paul Worsey, Dave McCool, Ryan Freeman, Chris Wolters, Rick Hines, John Bowles

Carroll Cave, located in Camden County, in south central Missouri, is one of the most significant caves in Missouri with over 12 miles of mapped passages and over 100 known but unmapped side passages. In the early 1990’s there was a breakdown of the originally excellent landowner/caver relations as the ownership of the only known entrance moved to a new generation and grottos squabbled for control. Subsequently the current owner of the natural cave entrance refused to grant anyone permission to enter.

Jan 1, 2003

By Geraldine Woods

I work for the State of Washington as an Explosives inspector. My paper will describe the mission of the Wa. State Dept. of Labor pertaining to explosives and the regulation of explosives in the State.Blasting safety is high on the public safety list and the regulation of explosive use and storage has been mandated through legislature. The Dept. considers pro-active partnering forexplosive safety preferable to after-the-fact citations for non-compliance.In some cases, the Dept. will issue civil citations with monetary penalties, meant to be a deterrant, of course, to blasters who choose not to comply with the explosive regulations of the State.The Dept. has also revoked and suspended blasting licenses. In some instances, the Dept. has allowed recipients of citations with monetary penalties to reduce the amount paid by attending technical training classes. The idea here, is to reduce the chance of reoccurence of unsafe blasting practices. The State of Washington partners with MSHA in the regulation of explosives use and storage in mines, pits and quarries in the Stateas well as working closely with law enforcement, State and local fire marshals, ATF,and is active in ISEE in part of it’s ongoing effort to promote explosive safety and establish communications in a nonadversarial way with explosives users. My paper will include some statistics on licensing in the State, pounds of explosives used, inspection numbers, numbers and types of complaints with information from the inspections resulting of these complaints. My paper will include examples of storage, both good and bad, examples and pictures of fly rock incidents, accidents, near-miss close calls, break-ins, thefts, and abandoned explosives. This paper may also include a brief summary of my opinion of explosive regulation and my job as a regulator, including examples of high and low points of the job, joys and frustrations.

Jan 1, 2002

By M. Ganster, H. Krenn

The mission of the project is the fast and cost-effective rehabilitation of decommissioned lignite mining and coal upgrading facilities. This is necessary to ensure the successful future utilization of these sites. On the one hand, for founding new industrial and commercial facilities and on the other hand for touristic activities.

Jan 1, 2013

By Pertti Paavola, Hikki Rasanen

This paper describes a very exacting tunneling project. Planning and technical realization of this service and transportation tunnel was especially difficult as a matter of vibration control, because the tunnel is situated only a few meters under Maria Hospital, which is one of the most busiest hospitals in Helsinki. In this hospital there are many departments for bedpatients, research and treatment with high-tech equipment, operational surgery and a big laboratory. Besides access tunnels are situated near several apartment buildings. The functionality of the tunnel required the placement of the access tunnels to be straight towards these apartment buildings for which special care for blast induced air pressure had to be taken.

Jan 1, 1997

By Stuart Brashear, Lee Schettler

The effect of water on several ANFO/emulsion blend ratios are documented by both physical observations and analytical testing to demonstrate the effect even small quantities of water can have on water resistant blends.

Jan 1, 1996

By Shazad Hosein, William Birch, Douglas A. Anderson

This paper will present the results of tests of a new method for assessing explosive performance using wavelet transform analysis of standard blast seismograms. The theoretical background of the method was presented at an earlier ISEE conference.

Jan 1, 2015

By Curtis G. Kremer

"New explosives initiation systems continue to be developed as new technologies make advancements possible. Due to recent initiator developments, explosives users now have the most reliable, accurate, safest and easy to use systems ever offered. Three initiation systems recentlyintroduced which offer significant improvement over standard electric and nonelectric initiation systems include Magnadet, EXEL high-strength shock tube, and Redundant two-Dath surface delay systems. These three systems will be discussed zn cecail with rmpiasis on their functioning, safety characteristics, ani specific application areas."

Jan 1, 1991

By Bruce Vandenberg

A 3D, PC based computer program is currently under development by Blasting Analysis International, Inc., to analyze the kinetics of full scale blasts with two or more high-speed motion picture cameras.

Jan 1, 1990

By Brandon Fryman, Josh Hoffman, Rhys Baker

A post-detonation debris collection project was led in conjunction with a large ammonium nitrate(AN) railcar detonation conducted by the Department of Homeland Security-Transportation Security Administration, Department of Defense-Combating Terrorism Technical Support Office, Sandia National Laboratories, and the U.S. Army Dugway Proving Grounds. This important work will aid in underpinning algorithms used in a Quantitative Risk Assessment (QRA) tool. The test also provided valuable data about the effects and consequences following an AN detonation. The test took place at the Utah Dugway Proving Grounds on April 27, 2018 and the debris collection was conducted the following two weeks with an average of 20 persons per day and an approximate total of 1,400 manhours. A paper was presented at the 2019 ISEE Conference on the collection efforts, challenges, and lessons learned. A complete data analysis effort was completed on the test data in 2019 that resulted in updates to the QRA Railcar Potential Explosion Site (PES)model and AN engine. The analysis included an assessment of the debris data resulting from the Derailed test. This paper is meant to serve as a summary of the analysis effort and findings and as an update to the previously presented lessons learned from the debris collection and analysis effort.

By Kevin Landey, Eric Gerst

Expanding blast patterns to near the limit of an explosives’ ability to do the necessary amount of work is a common practice to reduce drilling and blasting costs. Choosing less expensive explosives such as ANFO vs. emulsion, bulk product versus packaged product, etc. are also common cost savers. Both practices are only effective as long as the pattern geometries are accurately drilled. However, will pushing the limits on pattern sizes and explosive products produce consistent results at the face, minimize oversize, produce superior fragmentation, and improve crusher throughput? Sometimes, but no amount of explosives can overcome a poorly drilled pattern. Knowing the probable outcome of any changes in drilling and blasting is valuable in achieving success.

Jan 1, 2018

By Kenneth Eltschlager, Jim Ratcliff, Michael Mann, Edward Sheehan

The Appalachian Blaster Certification Delegation initiated a study to compare the consistency of measurements from blasting seismographs. Six blasts were monitored at surface coal mines in West Virginia, Maryland, and Ohio. A total of seven different makes were deployed during the tests, with as many as seven models from five different manufacturers compared during any one blast. Great care was taken to bury the geophones in identical fashion. The variations in seismograph readings were compared to the International Society of Explosives Engineers’ Performance Specifications for Blasting Seismographs. Between 4 and 125 Hertz, the ground vibration amplitudes should be within ±5% and airblast amplitudes should be ±1 decibel. For each of the three mutually perpendicular ground vibration channels and the acoustic channel, the median value of all the units was used as a baseline for comparison. The six blasts monitored had median peak particle velocities ranging from 0.42 to 3.47 inches per second (in/s) (10.7 – 88.1 mm/s) and median airblasts ranging from 124 to 135 decibels (dB). There were 46 seismograph recordings for the six blasts. Eighteen (39%) of the 46 maximum peak particle velocities varied more than ±5% from the median. A total of 138 (3 × 46) component particle velocities were recorded, with 50 (36%) of the readings varying more than ±5% from the median. For airblast comparison, 43 recordings were obtained, with seven (16%) varying more than ±1 dB of the median. Variances may be attributable to blasting seismograph differences, variations in field deployment, and relative locations of the geophones. Full waveform seismic and acoustic overlays for individual blasts showed encouraging conformity with some slight anomalies

Jan 1, 2015

By Lyle Dennis

Emphasis on increased production while maintaining rigid quality standards has necessitated a change in blasting technology at Dacotah Cement's limestone and gypsum quarries. The following three methods implemented during the past three years have yielded an increase in production through improved fragmentation.

Jan 1, 1996

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 Kate Satish

M/s Konkan Railways Corporation are constructing 760 kms long rail road in the Western Coastal Region of India. The rail road encounters 75 tunnels through the Western Ghats of India with a total length of 78.35 kms, the longest tunnel being 6.5 kms long. The tunnels are of horse shoes shape having a cross section of about 37 Sq.meters

Jan 1, 1996

By Sushil Bhandari, Amit Bhandari

Drilling and Blasting are core operations in a mine. They impact all the downstream operations and their costs. Digital technologies exist for optimizing both drilling and blasting for many years. However, these technologies have largely been non-integrated and non-real time. This gap results in sub-optimal drilling and blasting operations. Also traditionally focus has been on optimizing individual areas (drilling or blasting and subsequent subsystems). Industry has largely lacked real time or near real time integration available to the user in the field and in the office. In this paper, a case study is presented of a large global cement company using a cloud and mobile based platform across 17 of their mines consistently over a large number of users over a period of over two years. The use of a blast platform is detailed which include blast designs, blast data collection and the trends in terms of results. On the drilling side, this paper describes the ability to capture drill logs, plod reports etc. Also actual drilling information in the field using a mobile device and its real time synchronization with a blast designer to provide visibility of expected fragmentation and vibration levels based on the drilling done. Key parameters such as hole ID, design depth, actual depth, hole status, designed and actual charge (length and weight), designed and actual stemming length are captured. The case study also highlights the challenges in technology adoption and implementation in mining in drilling and blasting. Making drill and blast results predictable should be the desired direction. Also digital technology tool adoption has been seen at the biggest miners – not so much in mid-sized miners or drill and blast contractors. Benefits of this platform on the safety side are highlighted including predictions on safety parameters and appropriate alerts if blast safety parameter / clearance zones are not met. The safety parameters are made available visually to the operator using maps and / or on drone images. Future possible improvements in the digital technology platform at the site are also highlighted including greater possible automation.

By Patrick D. McLaughlin

Crater blasting techniques have had relatively little application in the surface mining industry. This is not surprising, considering the geometry required to efficiently use cratering. The more widely known blasting operations that employ some form of cratering are listed below.

Jan 1, 1992

By Thomas Hans Kleine

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