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By Gungor Tuncer, Ali Kahriman

This paper presents the results of ground vibration measurements carried out in Hisarcik Boron open pit mine located on the west side of the central Anatolia near Kütahya province in Turkey. Within the scope of this study in order to predict peak particle velocity level for this site, ground vibration components were measured for 304 shots during bench blasting. In blasting operations; ANFO (blasting agent), gelatin dynamite (priming) and delay electric detonators (firing) were used as explosives. Parameters of scaled distance (charge quantity per delay and the distance between the source and the station) were recorded carefully and the ground vibration components were measured for all blast events using 2 different types vibration monitors (1 White Mini-Seis and 1 Instantel Minimate Plus Models). The absolute distances between shot points and monitor stations were determined using GPS. The equation of square root scaled distance extensively used in the literature was taken into consideration for the prediction of peak particle velocity.

Jan 1, 2006

By Pierre-Alexandre Abeel, Charles Dowding, Justin Lueker

When blasting is eliminated as a cause of cosmetic cracking, often someone will ask, “If blasting didn’t cause the crack, then what did?” This paper describes detection by remotely operated instrumentation of the new cosmetic crack that was climatologically-induced. The measurement was obtained as a part of the development of Autonomous Crack Measurement (ACM) instruments to measure micro-inch response of cracks to both long-term, climatological, and dynamic, blast vibration effects. The crack occurred in the wall of a structure that was monitored for over 29 months and as such represents one of the longest periods of ACM observation.

Jan 1, 2015

By Craig Adams, William Poe

Introduction The United States Department of the Interior, Minerals Management Service (MMS) is mandated under the Outer Continental Shelf Lands Act (OCSL A) and the Energy Policy Act of 2005 to oversee leasing, exploration, development, and production of mineral and renewable energy resources on the Outer Continental Shelf (OCS). Under these authorities, MMS is responsible for permitting and overseeing an array of offshore operations; some of which involve the underwater detonation of explosive charges. Explosives are most critical for their use in the severance of bottom-founded piles and well components during the decommissioning of OCS platforms and well abandonment work.

Jan 1, 2011

By Robert Hopler

The 1800’s were a time of tremendous advancements in science and experimentation, and earthquakes were a subject of great interest. The meetings of the British Association for the Advancement of Science in 1853 and 1854 are good examples of this. The proceedings of the Association for the 1854 meeting includes a table entitled “Catalogue of Recorded Earthquakes from 1784 to 1850” which takes up 326 pages, and lists available information on approximately 3000 earthquakes. The 1853 proceedings have a similar table for earthquakes recorded from 1606 B.C. to 1783. In the 1854 volume there is a “Report of the Committee on Earthquakes,” which provides us with a view of the general state of the science. Excerpts from that report follow:

Jan 1, 2006

The breakage mechnism of a spherical charge greatly differs from that of the cylindrical charge used in underground mining. The advantages of the spherical charge could not be utilized until INCO Metals Company, Ontario Division, introduced large diameter holes to their operation.

Jan 1, 1978

By C H. Ryu

This paper presents a simplified two-dimensional numerical model of block fragmentation in a Jointed rock mass during the late or throw stage of a blast after wave effects have subsided. The model is based on the distinct element method. Examples illustrate the approach and allow for a comparison of effects of Joint patterns on fragmentation and resulting block motion.

Jan 1, 1986

By Alday B. Andrews

A computer program called Seiswise that predicts the character and intensity of ground vibration generated by surface blasting operations was developed and field tested. The program uses the time histories of one or more pilot shots in combination with various initiation sequences to construct synthetic seismograms which are examined to select designs that will produce low levels of ground vibration.

Jan 1, 1990

By Lars Osen

Both fragmentation and safety can be improved by following proper procedures in loading boreholes. Proper loading procedures such as primer location, borehole sealing, decking, and stemming along with the hazards of dropping on primers are presented. Discussions follow on the reason for the use of each procedure along with the possible consequences such as hazards, misfires, or poor fragmentation.

Jan 1, 1985

By Lee Julian

Ground vibrations generated by mine blasting must be controlled to comply with legislation and to protect sensitive local or site infrastructure. The consequences of exceeding imposed limits can range from negative publicity to structural damage to infrastructure. It is imperative that vibrations are controlled without compromising fragmentation and delivery of blasted inventory. General practice is to reduce the charge weight and the blast size as blasting approaches the sensitive structures; however such an approach results in blasting smaller volumes more frequently which places greater pressure on production to meet their targets.

Jan 1, 2014

By A B. Jr Nunn, W C. Gould

Good community relations is a major concern at this central Virginia aggregate quarry. In this paper, the authors describe the use of a new electric millisecond delay initiation system that has reduced the average level of vibration by 27% since its use began in late 1984.

Jan 1, 1986

By N L. Thomas

Hole size affects many factors which directly influence fragmentation in the muckpile and hence, the cost effectiveness of the entire operation. These factors include production capability, explosives and accessories efficiency and usage and drilling accuracy. In addition, hole size should be chosen to suit the geological conditions. The paper concludes that the optimum hole size is generally the largest that can be used commensurate with production and environmental considerations.

Jan 1, 1986

By Richard Dooley

This paper is one sided because it presents the problem, but not the solution. The problem of blisters (bubbles) and occasional tears in caisson liners occurred when blasting and we have not found a conclusive cause nor a preventive solution. (For back ground information, consult Techniques of Precision Blasting in the Excavation of Drilled Piers, by George Mosteller at the Sixth Conference on Explosives & Blasting Technique in Tampa, Florida 1980).

Jan 1, 1983

By Virgil J. Stachura, Larry R. Fletcher

The Bureau of Mines conducted a series of delayed blasting experiments at a West Virginia contour coal mine which resulted in smoother highwalls. The highwalls were smoother due to reduced overbreak and inherently safer due to reduced likelihood of rockfall. Reduced overbreak was accomplished by an increase in the highwall hole delay intervals which changed the effective delay pattern geometry and the direction of burden movement. Three combinations of blast delay intervals in the highwall holes were tested: 1) 50 ms longer than the nominal design, 2) 50- and 100-ms longer delays in the nearest two rows that form the highwall, and 3) 100 ms longer than the nominal design. The mine's nominal blast design was a flat vee formed by 17-ms surface delays between holes and 42-ms surface delays between rows, with 200-ms in-the-hole delays. All three test designs produced highwall improvements over the nominal design with only occasional exceptions because of geologic variations.

Jan 1, 1985

By Courtney W. Shea, Dennis Clark

Reckless blasting can have tragic consequences: The death of an innocent traveler, the financial demise of a coal company, and even criminal prosecution. In June 1993, a Tennessee coal mining company was blasting to loosen overburden at its surface mine. The mine was located immediately adjacent to the right-of-way of the northbound lane of Interstate 75. The approved permit included special precautions to be taken when blasting in the area closest to the interstate, including monitoring traffic so as to blast when the northbound lane was clear.

Jan 1, 1998

By Abraham Lindo

Panama’s current economical growth demands an increase in electric power supply; projected energy supply for 2012 exceeds the demand by as little as 2%. In an effort to comply with the demand, several different hydroelectric projects, promoted by the government, are currently under construction and each of them vary in generating capacity, construction design and complexity.

Jan 1, 2013

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 Kamal Wadhwa

Ever since the introduction of Liquid oxygen explosives in India in 1927, these explosives are being extensively used in the various mining industries such as coal, ironore, limestone, bauxite, magnesite etc. The earlier LOX compositions were based on cellulosic material of Weberlox series of French origin. They contained the basic ingredients of saw dust with an admixture of cork dust, some hydrocarbons and some metallic powders. However, there were some inherent defects in the soaking characteristics of these compositions, in as much as, absorption and retention of liquid oxygen in the cartridges were not properly regulated in the fine pores and in the inter-granular spaces inside the ingredients in a uniform manner.

Jan 1, 1989

By Robert Slivinski, Kyle Hobbs, Michael Stern, John Willox, Brad Jewson

Prairie Mines & Royalty Ltd. produces over 12 million tonnes annually of thermal coal for TransAlta’s Sundance and Keephills power stations from the Highvale Mine. This opencast mine is next to a lake and is surrounded by cottages and farms, which means that blast vibrations and air overpressure have to be kept to a minimum.

Jan 1, 2008

By Sterling Ziegler, Kameron Ray

Mining operations at a Wyoming coal mine were progressing to within 300 feet (91 meters) of a high pressure natural gas pipeline. Vibration levels from cast blasting were at a point at which standard designs would exceed permitted limits and could potentially damage the pipeline. Without a confident vibration model, mining would be unable to continue in the pit rendering an entire cut of otherwise mineable coal sterile. To safely blast in the area, linear superposition seedwave analysis techniques were attempted to be used to create a model that could accurately predict the vibration at the pipeline. Four signature holes were fired individually. The four signature waveforms were monitored at eight discrete locations to create thirty-two vibration data points. Two of the monitors were equipped with triggers enabling the calculation of p-wave velocity.

Jan 1, 2018

By Terry Matts, Henry Heidrich, Cluny Randell, Carl Kottmeier

Until 1990, all production of asbestos ore at Cassiar was by open-pit methods. With the impending exhaustion of open-pit reserves, a decision was made in February 1988 to continue mining underground, using the block-caving technique.

Jan 1, 1992