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By Brent Blanchard

Dallas/Fort Worth Airport recently took a major step in its fiveyear expansion project with the explosive demolition of the Hyatt Regency Hotel West. Built in 1965, the Hyatt Regency held the distinction of hosting five U.S. Presidents over the years and was reportedly one of the first hotels in the world to be built within an airport’s boundaries.

Jan 1, 2003

By Wenbo Lu

A combined method is present in this paper in analysis the dynamic stability of rock slope under the loading of blast induced seismic, in which, by combining the dynamic load calculating method of quasi-static method with the load inputting method of dynamic finite element method, such factors as the decay of seismic wave along its way of propagation, the frequency. amplitude. the phase difference of seismic wave, etc., can all be taken into account in analysis of the dynamic stability of slope.

Jan 1, 1999

By Bruce B. Redpath, Doug Crice, Rob Huggins

Over the last decade, instrumentation has been developed that allows the application of seismic reflection methods to groundwater and engineering problems. At the Geological Survey of Canada, we have been developing and testing shallow reflection techniques for mapping the bedrock topography and structure within the overburden. We have attempted to develop methods which can be implemented with a minimum investment in equipment and computing capabilities. The data are recorded on a l&channel engineering seismograph, using a single high-frequency geophone per channel, and a hammer or in-hole shotgun (“Buffalo gun”) as the seismic source. Processing and display of the data can be accomplished on an Apple II+ or IIe microcomputer and an Epson wide-track dot-matrix printer.

Jan 1, 1991

By John Yenter

"Unique blasting problems during reconstruction and expansion of 100 year old buildings toaccommodate gambling. Located on steep mountainous terrain and linked by narrowroadways, the towns of Central City and Black Hawk challenged blasters to exceptionalmeasures in order to control over_break, vibration, public exposure and damage to thecharacter of these historic mining towns. Utilities were also upgraded to fit demands of asmuch as 800% volume change in one year."

Jan 1, 1993

By Tristan Worsey, Nathan Rouse

The Florida legislature allocated funding for the Florida State Fire Marshal (FSFM) to review the applicability of the United States Bureau of Mines (USBM) Report of Investigations (RI) 8507 blast vibration limits with respect to Florida and its soils. The study also discusses whether the current blasting vibration limits set by statute are still appropriate, including a review of measured vibration amplitudes and frequencies, structure responses, and theoretical analyses of material strength and strains.

Jan 1, 2019

By Steve Dillingham

Here in the United States, as well as around the world, pose a daily dilemma - to wash or not to wash. Let’s face it, all trucks, especially our industry work horses - bulk trucks - get dirty. We all know that these units can be very expensive and washing them keeps your business investment looking new, improves public relations, fuels company pride, and facilitates equipment safety and preventative maintenance inspections.

Jan 1, 2001

By Paul Kunze

For some of us, the most disagreeable part of being the blaster- in - charge is doing the required paperwork. Cost coding on time cards, drilling reports, magazine inventory logs, and blast records all eat into our time. When all goes well, which I suppose is 98% of the time, the blast records are submitted and filed, probably never to be seen again. Sometimes a progressive operation will use the information documented in the blast reports to evaluate blasting effectiveness and improve results. When the report is consistently used in this fashion, costs can be reduced and other efficiencies will be realized. A blast report in times past was a simple form that mainly was used to keep track of the drill footage and of the powder used in the shot. However, as the population and consequences of careless blasting increase, multiple levels of blast documentation are now being required nearly everywhere, during all phases of the drill and blast process. We are now compelled to create preliminary blast designs prior to commencing work. We are required to submit pre-blast plans before each shot, and we need to generate post-blast reports that document the details and results of each shot.

Jan 1, 2004

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 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 Kenneth Eltschlager

Business says that location is a primary component of being successful. So too is the importance of location in blasting. For blast seismograph data to be useful, the location of the blast and seismograph must be clearly documented. Another location of importance is that of a nearby structure. Establishing the spatial relationships between the blast, seismograph and nearby structures, allows the blaster to correctly interpret the data, evaluate the performance of the blast and gauge the validity of any complaints.

Jan 1, 2004

By Lance McAnuff

The year 2001 coincided with the forty-fifth year of blasting-control specialization by the author. Commencing with the construction of the Saint Lawrence Seaway System in 1956 and continuing until the present time this career has spanned one of the most progressive and exciting periods in the still relatively short history of commercial blasting. The paper touches upon a number of the more interesting projects with which the writer was involved during those early days, including the removal by explosives of “Ripple Rock” the infamous underwater hazard to shipping which at one time inhibited ocean traffic along the Inside Passage between Vancouver Island and the mainland of British Columbia, Canada’s most westerly province. Various assignments involving incidents from devastatingly ,tragic to comically absurd are described, along with personalities encountered along the away, most of them readily recognizable as giants in the field of explosives engineering. Various stages in the evolution of state-of-the-art explosive products, initiation systems vibration monitoring equipment and limiting criteria are compared and some of the effects these have had on safety and productivity during the last forty-five years are analyzed.

Jan 1, 2002

By William Stewart

Recitations were taking place in the red schoolhouse at Orneville, Maine. It was winter and the snow lay deep on the ground, but some of the scholars were in bare feet, and only half as many hats hung on the pegs as there were potential wearers in the seats. That was forty years ago; and the pioneers of northern New England were more noted for their industry than for their possession of the fruits of it.

Jan 1, 2007

By W. J. Birch, A. Wetherelt

The scaled-distance model for blast vibration analysis is the standard method employed throughout the surface mining and quarrying industries to model Peak Particle Velocity (PPV) data. Although empirical, the method is widely accepted and through the simplicity of its application and ease of graphical verification is set to remain a popular option. The validity of the technique relies principally on the fundamental parametric assumption that blasting data is normally distributed. Throughout the evolution of scaled-distance modelling, this is an issue that has most often been presumed rather than proven (most likely due to the tediousness of the calculations involved). In the few cases when normality has been given some degree of consideration, the result has been the product of a simple visual inspection of frequency distributions: clearly unsatisfactory. However recently the soundness of this assumption has been brought into question, with obvious connotations for blast modelling in general. This paper considers this fundamental issue and seeks to investigate the normality hypothesis within the blasting context through an in-depth statistical analysis of what possibly can be described as an ‘ideal’ blasting dataset. This being a rare case study concerning an opencast coal site in England, where for the entire life of the site every single blast was monitored and recorded through the use of permanent monitoring stations. This has provided a unique ‘total population’ dataset of considerable size from which the assumptions of normality are put to the test.

Jan 1, 2005

By Steve Dillingham

The explosives business by nature is providing a specialized, valued service and associated products to a variety of customers whether mine, quarry or construction related. The level of performance demanded by the customer will typically coincide with his or her individual needs. Some will seek out the skills and knowledge of a blasting expert, while the focus of others is simply on production amounts.

Jan 1, 2003

By Bob Turnbull

The dictionary definition of calibration is: to determine by measurement or comparison with a standard, the corre c t value for each scale reading on a device.1 As a consultant or blast contractor, you assess risk every day. But, have you considered the importance of, and the risks associated with the calibration of your seismograph and the accuracy that is p rovided? Can your calibration pro v i d e r back you up in times of trouble and provide documented evidence that the equipment was functioning within specification? Can their calibration pro c e d u res withstand independent scrutiny and be shown to be traceable to a National Standards for accuracy of measurement? These are important documents that in court provide tremendous support that blasting and monitoring activities are conducted professionally and competently.

Jan 1, 2004

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 Ray Patterson

A planned modification to a cement kiln at the Holnam Portland Cement Plant near Florence, Colorado required the removal of a ring of cast-in-place (CIP) refractory lining. The CIP lining was approximately 14 inches wide, 12 inches thick and 38 feet in circumference.

Jan 1, 1999

By Alastair Torrance, George Boucher

The authors were involved in the Trial Blast work at Chek Lap Kok, the site of the new Hong Kong Airport. As part of that work a series of computer programs including 3x30, QFRAG, DESIGNER and 3DMUCK was employed to predict various aspects of the trial blast programme. These aspects included fragmentation and muckpiie shape. This provided an excellent opportunity for these programs to be calibrated, verified and compared under controlled conditions. The results indicated that computer simulation has reached a high level of sophistication and good correlation between prediction and measured results was found.

Jan 1, 1994

By M. Hagfors

On the underwater testing of explosives, the measuring system consists of water filled test pond, tourmaline based pressure sensor, measuring cable and measuring unit, which supplies the DC current to the pressure sensor. Depending on the length of the measuring cable, it is always possible that some signal damping may occur in case the measurements are carried out without the signal amplifier to keep the measuring system as simple as possible. Therefore the length of the measuring cable should always be as short as possible.

Jan 1, 2006

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