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Blast Site Security Involves: * Clearing the area * Controlling Access * Warning Signals

Jan 1, 2003

By Jonathan Heiner

Rio Tinto Bingham Canyon Mine started its South Wall Push Back (SPB) in 2011. This push back will mine through the only road to the pit bottom (the 10%). The pit bottom is the main ore sector for the mine and supplies about 80 to 90% of the ore. In late 2017 the mine set off a blast in SPB that created a small wedge failure on the high wall between SPB and the 10%. This wedge failure released a rock approximately 20 minutes after that blast that rolled down the wall landing on the 10% near and then contacting a light vehicle

Jan 1, 2019

By Francis O. Otuonye

An application of a time series and systems analysis modeling technique to blast vibration data is discussed. The vibration data was taken from a rock support structure and the surrounding rock mass at distances close (less than 15 feet) to a blast. The analysis technique provides quantitative information on the frequencies of ground motion as well as the frequencies and damping ratios of a near-field support structure.

Jan 1, 1994

By Nikolaos Petropoulos, Ulf Nyberg, Daniel Johansson

A series of signature boreholes were blasted to observe any difference between confined and free face blasts. Four geophones were used to capture the compressive wave. The conventional approach, i.e. the calculation of vectorized peak particle velocity (vPPV) did not show any difference. Also a wavelet transform was tested.

Feb 1, 2020

By Randall M. Wheeler

"Fourier analysis is a very powerful frequency analysis tool. However, it is frequently misunderstood and sometimes used inappropriately. Part of this workshop will involve the basics of Fourier series, the Fourier integral and finally the Fourier transform. Included will be a brief discussion of analysiswindows, including the box and Hamring windows."

Jan 1, 1998

By Thomas Rupp, Michael Siegwart

The paper presents the vibration and sound emission measurement campaigns carried out in 2007 in preparation for the Ceneri-Basistunnel construction. We also present the vibration measurement campaign conducted during the construction of the Zimmerberg-Basistunnel. Both tunnels form an integral part of the Swiss Federal Railway Company Neue Eisenbahn Alpentransversale project (NEAT). This strategic project comprised the construction of several new tunnels. Its aim is the improvement of the existing infrastructure. The improved infrastructure will be able to accommodate a larger volume of railway traffic that is also crossing the Alps at higher speeds. The construction of the Ceneri-Basistunnel commenced in 2006. Both the Zimmerberg-Basistunnel and the Ceneri- Basistunnel are located underneath densely populated areas. Therefore, noise and vibration emissions have to be kept to a minimum and must not exceed applicable codes of practice. In order to identify the most appropriate blasting strategy for the yet to be constructed Ceneri-Basistunnel, blasting trials were conducted. The paper presents the findings of these trials and identifies ways to reduce both noise and vibration emissions from blasting. The construction of the first phase of the Zimmerberg-Basistunnel took place between 1999 and 2003. While the first phase is already in operation, the construction of the second phase has been postponed (commencement originally due in 2007). The Zimmerberg-Basistunnel connects the outskirts of Zürich with the city centre. As the tunnel site was not located close to the surface near populated grounds, no special measures were needed to reduce the noise emissions from blasting. However during the construction of the tunnel, the vibration emissions from blasting were monitored on more than 50 locations on the surface. The paper presents the analysis of some of the data. An emphasis is placed on the appropriate synopsis and presentation of data for documentation purposes.

Jan 1, 2009

By Ray Jambakhsh, John Okell, Frank Cook

"In early 1988, an experimental study was carried out at the Inco's McCreedy West Mine inLevack, Ontario. The objective was to develop blasting techniques which would allow themine to maintain production targets and reduce blast induced vibrations and overpressure.Due to its close proximity to the town of Levack (approximately 900 feet), particularconcern was expressed as to the vibration and overpressure resulting from the undergroundblasting operations."

Jan 1, 1993

By Robert Hopler

Earthquakes, ground vibrations, seisms, or whatever you want to call the shaking of the earth, have been a fact of life throughout time. In spite of this, most people (except those unfortunate enough to live in seismicallyactive areas) have probably never felt this phenomenon, or if they have, only a very few times in their entire lifetime. However, when it does happen, nothing is more frightening than the sudden shaking of the earth beneath us - after all, we think of the ground we walk on as the unyielding, solid underpinning of our existence.

Jan 1, 2006

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 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 Kenneth Etschlager

The ISEE Blast Vibration and Seismograph Section provides a forum for the discussion of issues related to vibration and noise from mine, quarry and construction blasting. The section began as a Technical committee in 1995 to promote the accuracy of blasting seismographs. Currently five subcommittees exist within the section: Seismograph Standards; Seismograph Testing and Calibration; Vibration Limits, Technical; Vibration Regulations; and Program and Communications. Foremost, the Seismograph Standards section wrote the first two technical standards adopted by the ISEE. The historical accomplishments, current activities and objectives of the section are discussed.

Jan 1, 2003

By Gordon M. Matheson, David K. Miller

Possible impacts to the water quality and production capacity of ground water supply wells by blasting is a common cause of complaints for blasting contractors, mining companies, and local regulatory authorities. The major complaints of changes in well water quality include; turbidity, discolored water (red, brown, black, yellow and milky water), and nitrate and/or coliform contamination. The major complaints for changes in well water production capacity include: loss of quantity production, air in water and/or water lines, damage to pump, and damage to well screen or borehole.

Jan 1, 1997

By Jeffrey A. Straw, Joseph P. Jr Shinko

Ground vibration produced by blasting operations within South Florida, due to saturated soil conditions, generates surface vibration waves that may be measurable over distances of 3 - 5 miles from the source, and perceptible at distances of up to 2 miles. Structures above ground usually receive the most of the attention from the effects of high vibration levels. During construction of the Trilogy Development of the Swerdlow Companies, blasting was completed in a lake excavation immediately adjacent to the City of Pembroke Pines Utility Department, Deep Injection Wells No. 1 and No. 2.

Jan 1, 1994

By Douglas A. Anderson

The US Bureau of Mines, in RI 8507, has shown that blast vibrations at low frequency are more likely to cause damage and complaints than those at higher frequency. Since that publication in 1980, the Office of Surface Mining and many state and local regulatory authorities have incorporated frequency in their regulations for acceptable ground vibration from blasting. Even when frequency is not explicitly stated in regulations, it may become an issue in hearings or in court.

Jan 1, 1992

By Kenneth Eltschlager, Steven V. Crum, David E. Siskind

The Bureau of Mines was funded by the Office of Surface Mining (OSM) to determine how blast vibrations from a local surface coal mine were affecting homes in the towns of Daylight and McCutchanville, located in southwestern Indiana near Evansville. Although Daylight was about two miles from the blasting and McCutchanville four to five miles away, many residents claimed that blast vibrations were damaging their homes. At least one citizen felt that the vibrations worsened at the time the mine began cast blasting.

Jan 1, 1992

By Drew Martin

In March 2010 the Boral Linwood Quarry, Adelaide South Australia, implemented the blasting contractors Monte Carlo Blast Vibration Model as part of their blast design process. The Linwood Quarry was developing an area where blasting activities were marginally complying with the statutory vibration limits. Compliance to the statutory limits was only being achieved through the use of small blasts (less than 15 000 T (14 763 ton)) at a high cost to the quarry.

Jan 1, 2012

By W. J. Birch, R. Farnfield

Nuisance caused by perceived high vibration levels as a result of blasting on quarries and opencast coal mine is now the number one environmental concern of residents living adjacent to such operations. The intrinsic nature of blast vibration monitoring and prediction is that it is impossible to accurately forecast the vibration levels that will be experienced by a given blast at a given location. Thus it is that a statistical approach to the problem is the only viable option. Unfortunately, persuading local residents living adjacent to a project that requires blasting that this is the best way of safe guarding both their homes and their quality of life is not an easy task. Thus routine monitoring involving both operators and regulators play a key role in building trust. However, public confidence is often shaken when regulators and operators use two different blast monitoring instruments side by side to record a blast at a local resident’s house and arrive at different results. To make certain that this does not happen in future, what is needed is a protocol that ensures that any two different blasting seismographs give the same peak particle velocity values at the same observation point. To do this all the equipment manufacturers, regulators and relevant professional explosive engineering bodies need to be involved.

Jan 1, 2014

By David Sprott

The effect that underground blasting has on the stability of hangingwalls, pillars and other rock structures is an inherent part of Noranda's geomechanics and mine design program to improve mine safety and stability, increase productivity and reduce ore dilution. The blast monitoring program at Noranda Research aims to provide values of particle velocities and accelerations, delay firing times, and vibration periods to assist with practical blast design and controlled blasting techniques.

Jan 1, 1988

By Rob Farnfield, Mark Pegden

Old Cliffe Hill quarry produces between 4 and 5 million tonnes of crushed granite per year and is located in the county of Leicestershire in the East Midlands region of England. Blasting is carried out with bulk emulsion explosives in combination with either shock-tube or electronic detonators.

Jan 1, 2010

By D. Lee Petersen, Travis Davidsavor

The 2003-2004 expansion of a Duluth medical center required rock blasting adjacent to the existing structures, a Mn/DOT retaining wall and other urban structures. This case history describes the methods of a blast damage assessment, based on blast parameters, excavation locations, and critical vibration receptors (including surgical suites, a linear accelerator and a major retaining wall). The assessment concluded that blast vibrations could be controlled, by limiting charge weight, to eliminate impact at the critical receptors. Prior to construction, we conducted preconstruction surveys on structures susceptible to vibration damage. During construction, we reviewed submittals, observed test blasts, reviewed blasting logs and monitored blasting vibrations. Up to 13 seismographs were used simultaneously. Close coordination with medical center operations personnel was necessary to prevent impacts to critical medical procedures. Measured vibrations were clustered around the predicted values, and attenuated at the predicted rate. High-frequency blast induced ground vibrations induced low-frequency vibration of an adjacent MnDOT retaining wall. Medical center structures were observed to significantly attenuate the ground-borne vibrations. This paper was first published in the Proceedings of the 56th Annual Geotechnical Engineering Conference, 2008, at the University of Minnesota.

Jan 1, 2010