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By John E. Wiegand

"We will attempt to explain the basic workings of a modern seismograph and how the recorded data can be interpreted, not only for determining compliance to the regulations, but also in determining whether or not a seismograph record is accurate and valid. We will discuss some parameters that should be included in all seismographic recordings. We will give examples and use overhead slidesto show examples of both accurate and valid recordings, and tampered and inaccurate seismograph recordings. Much of the information presented will be basic in nature, and will reflect the opinions and personal experiences of the author. We ho'pe the listener will gain valuable information concerning the use and interpretation of seismographic data, as well as find interest and sometimes humor in the examples shown."

Jan 1, 1992

By Greg S. Williams, Richard W. Givens

This paper examines the effect of prill size consistency, internal panicle density, and oil absorbency on Ammonium Nitrate Fuel Oil (ANFO)-emulsion blends. By analyzing these physical properties of prill and the nature of the blending process, a mathematical model has been developed to theoretically predict blend densities. Calculated densities can now be compared to actual field densities to give an operator a basis for comparing various manufacturers’ emssions and Ammonium Nitrate (AN) during bid solicitation. The lowest priced emulsion and/or AN may not be the most economical, due to the impact of specific physical characteristics. These factors dictate the blending mechanics and resulting density yields for various mixes. The research was driven from observed ‘field’ mixing relationships and data. Ultimately, such a model can be an effective tool in evaluating blends from a cost and performance basis.

Jan 1, 1992

By Ron Glowe

This paper shows the potential of a new computer model, using the Glowe-Tech (GT) Tonnage Analyzer program to compare drilling and blasting results. This model uses the crushers and conveyors as measuring tools in aggregate quarries in the USA and Canada. All data is collected using commercially available kilowatt transducers and an analog input/output automation module. There are two areas of measurement used to compare results. The first area is the tonnage moved by key conveyors to show the split in products produced and the actual rate of production. If belt scale readings are not available then the Glowe-Tech Tonnage Analyzer can be used to convert kilowatts from the conveyor motor to tonnage. The second is the tons of rock crushed per kilowatt hour of energy consumption by the primary and secondary (optional) crushers. This modeling process works best if blasts are mucked and crushed in sequence. There are many other variables such as crusher types, crusher settings, screen sizing and actual geology in the pit that can influence the results, however if variables can be standardized then definite trends can be seen when comparing drilling and blasting results

Jan 1, 2005

By Marco Antonio Falquete

A novel spark-generating tube, containing no explosive in its composition, is evaluated and compared with conventional shock tube. The product overcomes a series of problems found in conventional shock tube technology. The technologic development had multiple aims: to avoid transport and storage costs associated with explosives, to be more environmental-friendly, to obtain a high-velocity, hightemperature spark whose thermal performance could overcome poor heat transfer to the delay charge by gas convection at shock tube end, and that could cross barriers such as tight kinks, close knots, cuts, extreme environmental conditions, and long-term hot explosive emulsion exposure. The product of this development is evaluated and compared with conventional shock tube in a series of aspects and performance tests, including spark thermal performance (ignition of tougher, low sensitive delay columns, spark gap test), propagation in critical conditions of use (kinks, knots, cuttings), extreme environmental conditions (long-term exposure to hot emulsion explosive, extremes of cold, heat, moisture, underwater exposure), safety features (ignition through flame, open fire), and security against terrorist acts. Due to the safe characteristics of the tube, a series of demonstrations will be performed during the presentation. In nearly all tests and aspects, the spark-generating tube exceeds conventional shock tube, and in the rest equals shock tube, making it a more reliable alternative.

Jan 1, 2005

By Gregory B. Poole

As part of a $3.5 billion program to improve the antiquated waste water system in the city of Atlanta, the Nancy Creek Tunnel is being constructed across the northwest portion of the city. This tunnel is over eight miles long and is being constructed using Tunnel Boring Machines (TBM) for the majority of the tunnel and conventional drilling and blasting for three shafts, starter and tail tunnels and four connecting tunnels, totaling 2400 feet in length. An extensive public relations program was developed for this project. A group effort by the owner, engineer and contractor produced a public relations program that both informed and educated the public of the anticipated perceptions and effects of the blasting and TBM activities.

Jan 1, 2005

By Thomas Barkley

Recent developments in hardware and software have made accurate measurement of Underground Face (Development) Drilling a reality. New and compact laser profiling equipment makes it possible to measure drilled material left on the face as well as the actual tracks of the holes drilled in the rounds. Utilization of these available technologies makes it possible to correctly define the drilling accuracy and the blasting pull. Through the use of actual face round measurements, I will show the level of definition and amount of information that can be collected.

Jan 1, 2003

By Michael D. McGill

The effect of fragmentation size distribution as it relates to front end loader productivity was evaluated by comparing loader cycle times to fragmentation size of the shot rock. At Gold Mine in Southern Utah, a gold deposit containing both limestone and sandstone formations were blasted in the same shot.

Jan 1, 1994

By Patrice Favreau

In 1990 the Noranda Technology Centre commenced a project to develop an interactive three-dimensional blast design system using a commerical computer-aided drafting and design package (CADD). The objective was to alleviate the blast engineer from the tedious and time consuming blast layout and design functions normally done by hand. This would allow more time for optimizing blast designs through assessing multiple options. Since several blast design software "tools" already existed at Noranda, the need arose to integrate all the applications into one overall system that shared one common database. The result is BLASTCAD.

Jan 1, 1992

By Douglas Bartley, Brian Wingfield, Robert McClure

Recent studies and limited tests indicate favorable results utilizing high accuracy electronic detonator technology over conventional non-electric pyrotechnic systems. This study discusses the application of this technology using the Daveytronic programmable system in an on-going production basis. The study quantifies the performance as it relates to fragmentation, excavation, vibration and productivity in an eastern U.S. aggregate mining operation.

Jan 1, 2001

By Dale S. Preece

"Detonation delay timing has been an important aspect of quality rock blasting for decades. Detonators that enable delay timing have improved over the years especially with the recent advent of precision electronic detonators. The positive effects of precision delay timing have been observed repeatedly in the field with improved fragmentation, heave and overall blast control. Three-dimensional computational capabilities in terms of software, material models and computer speed have recently made possible the computer simulation of multiple blast holes in a bench configuration with precise delay timing between holes. Some of the key physical phenomena enabled by precise delay timing include: 1) collision and interaction of stress waves produced by adjacent blast holes, 2) reinforcement of stress waves from multiple holes as they reflect from the bench face and ground surface, 3) reflection of stress waves from “dynamic free surfaces” created by previously detonating holes, and 4) deformation induced fracturing, cracking and fragmentation. Simulating rock blasting in 3D has shed light on the physics involved and is resulting in an evolution of our understanding of fragmentation mechanisms. Routine use of these 3D computational tools will result in a much better understanding of the complex physics set in motion by the rock blasting process and allow predictionof improved blasting."

Jan 1, 2009

By Ralph Dawson

The following additions to SLP-4 “ALWAYS AND NEVERS” have been approved by the Board of Governors since the last printing 6/97 and will be included in the next printing soon. They are also included in the Second Printing of the 17th Edition of the ISEE Blasters Handbook. Review them and apply those which might be applicable into your blasting program now.

Jan 1, 2001

By J E. (Boet) Coetzee

SAFEX International, as the name suggests, is a global organisation, which has the fundamental objective of improving the safety of operations concerned with the manufacture, storage, transport, and use of commercial and military explosives and pyrotechnic products throughout the world. It is a nonprofit making organisation of manufacturers of explosives from all parts of the world, founded in 1954 with the aim of exchanging experiences within the explosives industry. Every third year SAFEX organises a Congress during which members present papers on selected themes and discuss reports of significant incidents that occurred since the previous Congress. Admission is for SAFEX members only, thereby creating a safe environment for discussing problems “within the family”. The XV Congress will celebrate the Association’s 50th anniversary in Geneva where it was founded. An overview of the Congress indicates its structure and covers aspects such as the training event, technical seminars and the themes for the plenary sessions and associated workshops. The paper also highlights the special event for the chief executives of member companies and the review of incidents that occurred in the industry since the last Congress. The Congress concludes with a social programme for delegates and their partners on the last day.

Jan 1, 2005

By Raymond Chenier

British Columbia (BC) is Canada’s most western province. The landscape in BC is amongst the most beautiful and pristine in the world. Along with its beauty come vast mountain ranges, coastal rain forests, swamplands, deep river valleys, and almost every type of landscape imaginable. These all have, or at one time had, logging roads constructed. Some of these areas should never have had roads constructed due to poor drainage and unstable slopes, but some of the roads could be considered engineering masterpieces. To navigate a vehicle the size of an off-road logging truck down the side of a mountain with an 80°h side slope or greater can be a hair-raising experience. Not to mention coastal rains and/or high elevation blizzards. These factors collectively make logging BC’s most hazardous occupation. People are seriously hurt, sometimes even killed everyday.

Jan 1, 2001

By G. Gomez Ciments-Calcia

The sources of complaints by neighbours of the operating quarry are due to the 3 following causes : - Impulsional noises or air hoch wawes – Vibrations - D u s t How a blasting in a quarry operation is felt by neighbours cannot be measured solely by the various limits set by national and European regulations regarding vibrations and air shock waves (sound pressure).

Jan 1, 2002

With the ever increasing problems of narrowing profit margins, and increased liability, a solution/option to SEE members is needed. It is essential that all members understand the benefits of utilizing explosives in combination with other methods of achieving the required result on difficult rock or concrete removal projects.

Jan 1, 1995

By John Dean Smith

In order to discuss problem solving techniques for the future. we must first review the past. This paper will discuss the drilling and blasting problems and techniques that were used by .Imax Coal in the past few years, tn those of today.

Jan 1, 1991

By S. J. Dillingham

As we enter the new century and close out the old, it has become standard procedure for most blasters to complete a blasting log or shot report following a blast. However, how can you be sure these completed blasting logs are worth the paper or electronic space they occupy.3 Is the recorded data accurate and meaningful? Will the blasting logs stand up under investigation? This paper will attempt to define the purpose of a blasting log, illustrate common mistakes, discuss potential problems, and indicate steps that a company or individual blaster can take to improve and protect against costly errors. The end result will be a reminder of the importance of accurate documentation following a blast that must be given the same individual effort as went into the blasting itself. This paper will also attempt to achieve a proactive training resource to improve the use of blasting logs. A completed blasting log is, quite possibly, the only witness to the overall credibility of the work of the responsible blaster. The log may remain perpetually silent, only to end up in a file that is moved progressively with time to various levels of long-term storage. But, will this silent witness be ready to speak out should a concern arise from the blasting ? Will the blasting log communicate with authority and credibility, or will it be ridiculed by investigation and silenced in shame with costly adverse results for the blaster and company? It is not enough to simply complete a blasting log. The information it contains must be accurate enough to stand the test of time and arduous scrutiny. Unfortunately, most blasters and their associated blasting companies do not realize the status of the silent witness until it is too late.

Jan 1, 2000

By Lawrence W. Gubbe

Air blast associated with detonation of explosives in mining, construction or military applications is often responsible for complaints by people who live or work in the vicinity of the activity. Most often, the complaints are based on the perception that vibration caused by the airblast damaged one or more residential buildings that may be located within several hundred feet or several miles from the blast site. The potential for airblast to cause damage is related to the amplitude and frequency of the airblast overpressure wave at the receptor. Amplitude and frequency of the overpressure wave are, in turn, dependent upon the type and amount of explosive detonated; the degree of confinement; the distance the wave travels; the topography between the blast site and the receptor; and, atmospheric conditions. It is well known that, as the result of atmospheric focusing, the amplitude of airblast overpressure that exists relatively far from the blast site may be substantially higher than the amplitude associated with the attenuated wave in an isotropic atmosphere. Two methods are available to predict baseline overpressures 1) the Sandia Laboratories, Atomic Energy Commission method as extended by the Naval Ordinance Laboratory (NOL method) and the Ballistic Research Laboratory method (BRL method). These methods are developed by different techniques, are based on different idealized atmospheres and predict widely different results. The amplification factor applied to account for the effect of focusing must be consistent with the method used to predict the baseline overpressure. Theoretically, the amplitude of the overpressure at distances several miles from the blast site could be more than 25 to 100 times the amplitude of the attenuated wave predicted by the BRL method. However, based on comparisons with measured overpressure data is probably less than approximately 3 times the amplitude of the attenuated wave as predicted by the NOL method. This paper is based on research conducted as part of investigations of airblast damage complaints associated with an accidental explosion near Eveleth, Minnesota and with the disposal of military explosives by detonation at the Sierra Army Depot near Herlong, California. The techniques available for estimating the airblast overpressure that might be generated at various distances from the blast site and criteria for evaluating the potential for damage are examined.

Jan 1, 2004

By Chris Breeds, Larry Leone, Jerry Wallace

Project Owners typically require General and Detailed Blast Plans when blasting close to important structures and specify the maximum allowable peak particle velocity for each potentially affected structure. Low, residential level PPV limits may be specified which significantly restricts the potential for blasting to be effectively used. Contractor’s responding to these contract conditions typically cite historic case studies which may, or may not, apply to the specific situation and/or types of structures for which limits have been set. A long submittal cycle typically follows.

Jan 1, 2010

By P D. Katsabanis

This chapter describes the principles for the derivation of the equations for a detonation wave. The importance of the equation of state for the detonation products is demonstrated and commonly used equations of state are discussed. Furthermore a brief introduction to the TIGER code is presented.

Jan 1, 1991