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By Steve Colburn

The new CRITERION Survey Systems utilize both theodolite mounted and hand held reflectorless distance meters. These are eye safe, easy-to-use, and specifically designed to endure the harsh environments characteristic to the mining, quarry and explosives industries. Survey data collected by the systems is digitally stored in a ruggedized data collector and then processed with a specialized, new Windows-based interactive software program, which can be run on any standard PC.

Jan 1, 1995

By David P. Reddick

"Suncor Inc. Oilsands Group mining operation in Northern Alberta, Canada, has been blasting to loosen the oilsands to increase production and decrease maintenance of the bucketwheel excavators for over twenty years. In 1991 an area of the mine was encountered which had a working face of 130 feet rather than the usual 20 to 57. In order to maintain production objectives, the planning and blasting departments of the mine took on the task of blasting as much of the working face as possible. McGinnis Rathole Drilling Company provided the drilling for the project and Mining Services International (MSI) delivered the bulk explosives to the boreholes. It is believed the resultingblasts exceeded several known records in production blasting."

Jan 1, 1992

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 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 Yang Jun, Qu Mei, Zheng Yao-wu, Chi Li-yuan

Due to the necessity of the prediction of blasting seismic effect around strip mine bench blasting area, the paper provides a method to predict the blasting seismic effect by employing the superposition of seed waveform at different monitoring points. The method assumes that blasting vibration waveform per hole is similar to seed waveform at monitoring point. Therefore seismic wave consists of the superposition of the waves from all of blast holes. Firstly, via sensors multiple seed waveforms can be achieved at different distances from signature hole. Then, by using the given dose and the distance, the vibration waveform of a certain blast hole can be calculated by the corresponding seed waveforms. Finally, the initiation delay time interval per hole is added to the propagation time to the predicting point. The predictive waveform at the whole blasting area can be obtained by superimposing all of the single waveforms. Considering the vibration waveform of a single blast hole changes greatly with the distance, under different distances condition the seed wave employed to superimpose is achieved from the similar distance. The experiments demonstrate that based on the method the predictive vibration waveform and spectrum are basically consistent with monitoring results around near-field blast. Compared with single seed wave method, the superposition method of multiple seed wave is more reliable to predict the duration of blasting vibration, the peak particle velocity, dominant frequency and frequency distribution.

Jan 1, 2015

By Robert Hopler

Some few years ago, when the cruiser “Brooklyn” was passing through the fairway to the southwest of the Battery, the ship being fully equipped with stores, etc., and therefore at her maximum draft, she grounded quite heavily upon some obstruction, and received injuries which necessitated her docking at the Brooklyn navy yard, where extensive repairs had to be made on her damaged bottom.

Jan 1, 2007

By Bobby Dupree

I remember a big problem with a seismograph in the winter two years ago. In response to a citizen’s complaint I placed a transducer near the corner of a two-story home. It was a pretty nice day for the winter months, the people were pleasant, and I had no problems digging a hole to place the transducer.

Jan 1, 2004

By Stacy Loizeaux

The Beirut Hilton Hotel, which was built in 1975, but never occupied, was imploded on Sunday, July 14, 2002 by Controlled Demolition, Inc. (CDI) of Phoenix, Maryland and their client, Optimal Engineering Consulting & Contracting, SARL, (OECC) of Antelias, Lebanon to make room for a new hotel. Twenty-seven years ago, just days before the grand opening, the Hilton Hotel became the site of fighting in Lebanon’s Civil War. Christian and Muslim militiamen fought room to room for control of the building and other nearby hotels. The Hilton, two other major hotels and other high-rise buildings were ravaged by the fighting. The building was one of the three major hotels badly damaged, but not rebuilt, in Lebanon. Located in the City Center, the Hilton stood out in a major redevelopment area which, in recent years, had erased the scars of the 15 year long Civil Wa r.

Jan 1, 2003

By Roger "Dean" Skaggs

Mechanical rock drilling is about 150 years old, and the fundamental principles of augering, penetration and dragging, pressure and rotation, and percussion have not appreciably changed. Surface mining blasthole drilling employs relatively shallow blastholes (to about 100 to 130 feet or 30 to 40 meters) with respect to the blasthole diameter and hole alignment while problematical is not a major universal problem. Modem underground mining methods are spacing development levels up to 400 feet (130 meters) apart, to take advantage of high powered mechanical drilling methods, requiring very long blastholes compared with surface mining. Blasthole alignment is a major problem in underground mining and this paper will address the aspects of percussion bit design which impact on hole alignment and drilling and blasting costs, i.e. bit geometry, cuttings removal, penetration-retraction.

Jan 1, 1997

By S. Paul Singh

Rock is a heterogeneous medium, a fact often ignored during blast design. In reality, the rock mass characteristics have a controlling influence on the outcome of a blast. If the optimum blasting results are to be achieved over a range of rock mass conditions, it is prudent to understand the role played by the geological features of a rock mass in producing overbreak around the periphery of an excavation. The field work was performed in a drift located in a geologically dominant rock mass and also included observations and assessment of blast damage at several operating mines. The blast damage was estimated on the basis of the half cast factor. The effect of rock strength, rock quality designation, orientation , frequency and aperture of joints, number and thickness of layers and hydrogeological conditions on blast damage has been described.

Jan 1, 2000

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

I was lucky to land a job in the powder business. I was looking for some way to support my wife and first child to be when I saw an ad in the Hercules magazine, “Explosives Engineer” for technical representatives. I answered the ad in hopes that a geologist might find something else to do besides sit oil wells or “doodlebug” for oil. Both of these occupations I had tried and while the money was good the life was a bit erratic. The Army also wasn’t made for a guy who asked too many questions although my two plus years in uniform were interesting and in a few cases fun.

Jan 1, 2004

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 X Meng, W. A. Hustrulid, M. K. McCarter

Rock excavation in both surface and underground mining is largely accomplished using the drill and blast technique. At the perimeter of such excavations, cautious blasting procedures are often employed to minimize unwanted damage to the remaining rock. Of the several different techniques available, the use of explosive charges with a diameter smaller than the holes in which they are introduced (so-called decoupled charges) is the most common. In spite of the long and widespread use of the technique, a technically sound basis for relating the borehole wall pressure to the explosion pressure is still lacking. Such a relationship is required for optimal design

Jan 1, 2005

By Timothy Stark

Blasters are usually strictly liable for injury or damage caused by flyrock (trespassory invasion) and blast-induced vibrations (non-trespassory invasion). The application of strict liability to non-trespassory invasions has resulted in significant litigation that has hampered the use of blasting and the blasting industry. Stark (2002) proposes that blasters should not be held strictly liable for non-trespassory invasions but should be liable only if their conduct is proven to be negligent. This change in legal standard was proposed because improvements in blasting technology over the last thirty years allow blasting to be conducted without substantial risk of harm to property and thus the amount of harm imposed by a blast can be related to the level of care exercised by the blaster. It is anticipated that a negligence standard will reduce the amount of litigation because a plaintiff will have a greater burden to overcome. To facilitate the acceptance of a negligence standard by a court of law, this paper summarizes the standard of care using the 1977 Surface Mining Control and Reclamation Act, extensive U.S. Bureau of Mines research, and current blasting techniques, such as blasting mats. It is important for the blasting industry to promulgate a standard of care so a judge can feel confident that blasting can be routinely and systematically controlled and if the legal standard is changed from strict liability to negligence a subsequent judge or jury will be able to evaluate the level of care exercised by the blaster. This paper also suggests that the industry and/or ISEE develop and disseminate a comprehensive standard of care that courts can use to further justify a change from strict liability to negligence and evaluate the standard of care.

Jan 1, 2003

By G. R. Adhikari

Step 4: Selection of explosives and initiation system Various types of explosives are manufactured in India and a wide choice is available among them that include nitroglycerin based explosives, slurries, emulsions, ANFO (ammonium nitrate mixed with fuel oil) and heavy ANFO. The choice is also available between cartridged and bulk loading systems. In Indian mines, much importance is unduly given to the cost of explosives alone which is not conducive to optimization of blast design parameters. The concept of energy per meter of blasthole and the way in which the total explosive energy is partitioned between shock and heave is not considered in the prevailing practices. Besides, very little efforts are made to objectively evaluate the performance of explosives for a given site condition. Tailoring explosives is limited to changing the density of the bulk explosives. Cartridged explosives are still being extensively used in large operations where bulk explosives should be the preferred choice.

Jan 1, 2002

By Steve Dillingham

In every aspect of conduct, on the blast site or off, the issue of credibility is raised. Promises are made, commitments are satisfied, safe practices are obeyed, communication is maintained, and proven procedures followed. Only by fulfilling these objectives, are we deemed trustworthy and reliable - in other words - credible. Unfortunately, at times, we fall short of achieving our goals. Whether intentionally or accidentally, everything is not completed according to plan or accuracy. On the blast site, falling short of achieving such goals may contribute significantly to a chain of events that can potentially produce accidents. At the very least, a blaster’s credibility will be jeopardized. The fact remains that the blaster that continuously conducts business in a professional manner will less likely find him or herself as a defendant in future claims.

Jan 1, 2003

By Satish Kate

Indian limestone mines which are highly mechanized in operation and supply limestone to the cement plants have been quite successful in devising ways and means to optimize blasting parameters, so as to have best fragmentation, powder factor, and cost of excavation. In primary blasting mechanized or manually mixed ammonium nitrate Fuel Oil is quite popular in dry holes, and in case of watery holes conventional packaged slurry/emulsions are being used. In order to avail the low density characteristics of the ANFO, some limestone mines have also used Saw Dust and Rice Husk along with ANFO. A number of field trials have been undertaken to explore the suitability of mixing rice-husk and saw dust with ANFO. Presently, about 10% of rice husk/saw dust is being used only to expand the explosive column. The main technical consideration for the use of saw dust/rice husk, has been to reduce the final density and increase the occupancy of explosive in the blast-hole. This not only lowers the detonation pressure in the blast holes, but also reduces cost of explosive without compromising on the fragmentation quality. Besides, with sleeping of the charge there is no substantial fall in the blast quality.

Jan 1, 2006

By : D. Lawrence

Certain blasting applications are more prone to the generation of significant levels of nitrogen dioxide post blast fumes, more commonly referred to as after blast smoke, generally ranging in color from dark yellow to bright red. This paper reviews basic background chemistry defining the observed fumes and attempts to correlate geology, blast design, and explosive composition effects on the level of nitrogen dioxide that can be observed in various blasting conditions. Additionally, a test setting for evaluating the generation of post blast fumes is presented with pertinent test data detailing generic explosive formulation modifications which effect the overall level of post detonation generation of nitrogen dioxide.

Jan 1, 1996

By M. Roy

Safety and stability of underground coal mine workings are always in danger when opencast mines are operating in close proximity. A study was conducted to investigate the level of vibration generated from opencast blasting at similar distances on the surface as well as in the nearby operating underground coal mine openings. Eight blasts were performed and nineteen vibration data were recorded on the surface behind the opencast blasting face and also in underground openings at similar distances. It was observed that magnitude of vibration recorded on the surface were more than those recorded in underground.

Jan 1, 2007