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By Paul Worsey, Ron Ecklecamp, Scott G. Giltner, Ronnie Inman, Terry Drechsler

A blast monitoring program conducted at Chemical Lime Companys new lime calcining facility near Ste. Genevieve, Missouri is discussed. The purpose was to develop blasting criteria for the construction and operation of the lime plant within the quarry operated by Tower Rock Stone. Further, it was imperative to accommodate production requirements into the blasting criteria. The major concern was the effect of blasting on the curing of green concrete during the construction of the storage silos and kiln stacks. In addition to discussing the susceptibility of curing concrete to blast vibrations, the paper also details how this varies with time.

Jan 1, 1996

By H Fukui, K Ichikawa, K Aikou, E Suzuki

An electronic delay detonator (EDD) consisting of a digital-base electronic delay module and a conventional instantaneous detonator module, designed for series connections with a special adjustable-output blasting machine, is described and shown to provide a delay time accuracy some four to twelve times higher than that of pyrotechnic millisecond and decisecond delay detonators, together with the other performance characteristics necessary for practical use. Also described is a blasting design system which allows effective reduction of ground and air vibration, through the use of EDDs with optimum delay times as determined by accurate computer simulation based on wave form and other data obtained from an on-site single-shot test blast.

Jan 1, 1989

By Earl C. Hutchison, Gene Smith

Extensive blasting was required to construct an underground tunnel for a 90 inch sewerage relief line. The tunnel and required excavation extended under an upper middle-class residential area in Atlanta, Georgia for more than a mile and a half and required the use of more than a half million pounds of explosives in the immediate vicinity of houses and residential apartments valued at more than 16 million dollars. Other houses and property valued at more than 80 million dollars were within range to claim blasting damages. An effective blasting damage control program was carried out which limited the number of blasting damage claims to less than 2-1/2% of the total number of potential claims. All but three of the small number of blasting damage claims which were made were effectively denied without any resulting legal actions and less than $3,800 was paid for settlement of the three claims.

Jan 1, 1981

By Frank Hirthammer

Since the introduction of the Explosives Track & Trace in Europe in 2014 for manufacturers and 2015 for end-users, a lot has changed in all areas of the supply chain and the use of explosives. The regional associations, manufacturers' organizations, and trade associations have proven that it is possible to overcome a hurdle, that looks almost impossible in the beginning, through consistent cooperation. The paper gives an insight into the problems involved in introducing such a requirement, identifies ways and solutions, and concludes them. When looking at the current situation, the paper describes the process by which a prescribed change in business processes are transforming into a solution that increases productivity, security, and handling.

Feb 1, 2020

By Frank Hirthammer

Since the introduction of the Explosives Track & Trace in Europe in 2014 for manufacturers and 2015 for end-users, a lot has changed in all areas of the supply chain and the use of explosives. The regional associations, manufacturers' organizations, and trade associations have proven that it is possible to overcome a hurdle, that looks almost impossible in the beginning, through consistent cooperation. The paper gives an insight into the problems involved in introducing such a requirement, identifies ways and solutions, and concludes them. When looking at the current situation, the paper describes the process by which a prescribed change in business processes are transforming into a solution that increases productivity, security, and handling. It shows examples from daily work, in which possibilities for optimization, improved quality assurance, and work facilitation are explained. It presents the resulting potential by comparing process flows, before and after the introduction of Track & Trace solutions. What challenges will we face in the future concerning the use of T&T solutions? Will the tracking of explosives become the norm worldwide? What are future hardware and software developments to be expected? What impact will this have on the global supply chain?

By G. F. Revey

When rock blasting occurs near new concrete of varying age, engineers representing project owners often express concern that vibration from the blasting will crack nearby concrete. Regulations and/or specifications for civil construction projects usually include particle velocity vibration limits intended to protect concrete. In some cases specified limits are unreasonably low and needlessly restrict and increase the cost of excavation work. This paper discusses how methods of predicting resulting flexural strains caused by blast-motion can be used to develop safe and reasonable PPV limits to protect new concrete. Three case histories demonstrating how these evaluation techniques were used to establish higher PPV limits designed to protect concrete of various structural condition are also presented.

Jan 1, 2006

By Navid Mojtabai, Jaak J. K Daemen

Some facilities require ground vibration limits that are far below typical vibration levels of interest in most blasting situations. A possibly extreme example of such a facility might be the proposed SSC (Supercollider Super Conductor) high energy particle study system. The applicability of conventional blast vibration predictors for such a low amplitude vibration is highly uncertain. For this preliminary study, a series of field measurements are made, and the results integrated in a set of vibration predictor equations. Ground vibrations induced by blasting operations at one proposed SSC site are monitored at close distances (hundreds of feet), intermediate distances (miles), and long distances (tens of miles) from the blasts. Peak particle velocities are recorded at short distances, ground displacements at other points, as well as frequencies. Theoretical analyses are performed by integrating all data in a variety of ground vibration predictors. From the statistical analysis of the data, ground motions at various points along the ring site are predicted for a given charge weight. The approach taken appears adequate for making tentative estimates of exceedingly low amplitude vibrations at great distances from mine blasts.

Jan 1, 1987

Vibrations are of concern not only for the safety of surface structures but also for the stability of underground openings. A number of parameters affect the intensity of vibration in underground openings due to blasting in adjacent opencast mine viz. total explosive weight detonated in a round, maximum explosive weight per delay, propagating media, depth of cover, RMR of the roof rock, age of the underground openings etc. Although a few researchers have tried to study the impact of parameters stated above, the impact of initiation sequences on generation of vibration in underground openings due to opencast blasting has yet remained untouched. A study was planned to evaluate the impact of initiation sequences on the magnitude of vibration in underground openings due to blasting in opencast mine. Nine production blasts with top and bottom initiations were performed at Samleshwari opencast project in India and eighteen vibration data were monitored in the roof of Hingir Rampur underground colliery in both the initiation sequences. The result indicated that the vibration produced in the underground openings from bottom initiation was lower than that of top initiation.

Jan 1, 2003

By John M. Feasler

Since the advent of NONEL shock tube, the signal transmission invention developed by NITRO NOBEL AB of Gyttorp, Sweden, we have seen the following application in the United States: (1) NONEL PRIMADETS - Non-Electric Blasting Caps for underground use, available in long period delay and millisecond delay intervals. (2) H.D. NONEL PRIMADETS - A rugged model of the underground unit designed primarily for use in quarries, coal strips, and open pit mines.

Jan 1, 1977

By Oldrich Machacek, Gary R. Eck

The underwater detonation test method has been long recognized as a useful tool for the evaluation of the energy release and relative effectiveness of commercial explosives. In this study, underwater energy tests were performed for emulsion and watergel commercial explosives in comparison with ANFO. Heavy ANFO type blends based on emulsions and watergels were also investigated under and without confinement.

Jan 1, 1990

By Ken Eltschlager, J Silva Castro, J. M. Hoffman, Braden Lusk

This case study focuses on analysis of sounds inside a house induced by blasts as result of surface mining coal in West Virginia and how to better communicate technical information to the public. The field study included a house wide vibration and sound monitoring system installed in a home which was subjected to blasts at varied distances and direction. The structure response was separated into ground vibration and airblast induced movement due to the differences in their times of arrival. This signal was then compared to the sounds recorded to determine which component of blast (ground vibration or airblast) induced the maximum sound. Findings shows that blasts at distances less than 762 meters (2,500 feet) had maximum sound responses from both ground vibration and airblast. While for blasts beyond this distance the maximum sound response was caused by ground vibration without exception. The kitchen generally created the most sound. The second phase of the study was to gauge the public’s response or preference to technical information. Three hundred and forty eight (348) telephone surveys were conducted in Logan and Boone counties West Virginia. Based on the survey, the public prefers units of pounds per square inch (psi) for airblast and millimeters of displacement for ground vibration. Ultimately a public relations plan was developed based on the results.

Jan 1, 2012

By Winfried Rosenstock, Carlos Orlandi

Along the Pacific West coast of Latin America there are several large operations of metal mining activities. To mention only a few: Chuquicamata in Northern Chile moving daily approximately one million t of copper ore and waste, Cerro Verde near Arequipa in Peru, or lanaccocia. Apart from the coal deposits in north-east Columbia it is mainly to deal with metal-mining, which has due to geographical reasons relatively high cash-cost. This sector of mining is traditionally severely depending on the world-market.There are reasons to believe that the world-market will remain on a low price level and some analysts predict that in general the price-level will continue on low basis for the next decade. The cash-cost factor becomes therefore even more important as it already is. The goldprice development during the year 1999 illuminates that market changes can quickly lead to a severe crisis which forces the shutdown of mines with cash-costs close to or above the present market price per ounce. The breakdown of the cash-cost shows, however, that there are ways to overcome even the crisis like it struck the low-grade open pit goldmines around the world. Especially hitherto the “Electronic Option” is the only solution as the possible reduction using advanced technology based on the application of electronic detonating systems and newly developed special ignition procedures. The electronic option will lead to tremendous cost reductions similar to the results of research operations Thiess Contractors, Brisbane, Australia have carried out in Australia in 1998 and 1999. The electronic option allows a comprehensive integration of side effects of the blasting process which in the past could not have been achieved so far. Electronic initiation can achieve secondary effects which have an additional and positive impact on the level of costs. Appropriate application can enhance the production of material which will reduce the primary crusher costs or even make a primary crusher operation obsolete.

Jan 1, 2000

By A Lance McAnuff, Andrew Curic

Until relatively recently, underwater blasting operations for channel deepening, dock construction and pipeline crossings of lakes, rivers and streams were conducted without much regard for the potential side-effects on aquatic organisms.

Jan 1, 1997

By Andre Pienaar, Larry Wilson, Clive Dawkins

The development of implementation of cost effective emulsion explosive and portable pumping system for the replacement of package explosives in the deep level gold mining environment. A number of versions of portable pumps will be presented, demonstrating continuous improvement on these systems. Data on reliability of units in the field will be presented.

Jan 1, 2009

By Michael A. Barbaglia, Mark William Withey

The lift shot is an essential blast design in the execution of mine creation and expansion plans. Whether it be opening a new quarry, creating a new level in an existing operation, or for control of water, lift shots are utilized to create the desired results. Lift shots by their nature differ from conventional production blasts because they have no free faces for relief of the blast. Due to this fully confined state, the primary direction of the rock movement is vertical, and the potential for excessive vibration and fly rock generation is great.

Jan 1, 1994

By Chantale Doucet, Yves Lizotte, Alan Cameron

A joint Federal Government-Industry research project on the effect of geology on the fragmentation of rock excavated by blasting in underground developments was conducted at the CANMET Experimental Mine, near Val d’Or, Quebec. A total of thirteen (13) blasts were studied from November 1994 to February 1995. The analysis of each blast was divided into three stages: pre-blast characterization, including structural mapping, assessment of Rock Mass Ratings (RMR), Tunneling Quality Indices (Q), blast design documentation; blast characterization comprising blast vibration monitoring and analysis; and post-blast assessment comprising fragmentation assessment by digital photoanalysis, calculation of half cast factors and measurements of bootlegs.

Jan 1, 1996

By Denise Clarke

Homeland Security Qualifications (HSQ) personnel were instrumental in developing the UK’s suite of Explosive Substances and Articles (ESA) National Occupational Standards (NOS) (also known as "competences") on behalf of the Standards Setting Body for Explosives, Munitions and Search Occupations (SSB for EMSO).

Jan 1, 2013

By D K. Joyce

Large diameter boreholes have become increasingly popular in underground mining. Drilling equipment can drill full rings, including vertical upholes. Special techniques are required to load upholes of three inch to eight inch diameter. The current methods for loading AN/FO and bulk or packaged emulsions are described.

Jan 1, 1988

By P Cotton, N Cox

The Brisbane City Council has implemented a program of continual improvement at its Mount Coot-tha Quarry in the heart of Brisbane, Australia. The program has been underway for the past 6 years, and has resulted in very significant improvements in terms of both the cost effectiveness of its operation, and in terms of its environmental impact on nearby residents. The work has included a focus, amongst other things, on blasting efficiency, and has challenged conventional thinking in terms of the size of blasts fired, the frequency of firing, the diameter of blastholes, and the use of bulk emulsion or slurry explosives.

Jan 1, 1995

By Richard D. Love

Competition in the aggregate industry of the 90's will be an over increasing really. With this in mind a quarry manager should always be comparing new and innovative concepts to increase productivity and reduce operating costs. In this paper, the author will present a comprehensive history of a drilling and blasting program that achieves these results. By employing proven methods and implementing new concepts, this program was proven to be a success over a ten year period.

Jan 1, 1991