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By D Wilson, R R. Vandebeek, R A. Bowes

"As business opportunities are sought around the world, the explosives industry must oftengrapple with the United Nations Transport of Dangerous Goods Recommendations.Canadians have problems in this area that are similar to those of other countries. Thispresentation outlines, through a case study, how a container for shipping ""explosives"" wasdesigned, tested and approved for use by the Chief Inspector of Explosives, the""Competent Authority"" for Canada."

Jan 1, 1993

By Anne Charline Sauvage

Blast designers and blasters need to know the rock mass influence on blast to increase explosive effi-ciency and to optimize costs, but also to succeed in limiting blast emissions (vibration, overpressure, flyrock) This paper presents an applied approach which makes it possible to structure the information con-cerning the rock mass and the blasting.

Jan 1, 2013

By Dennis Dobson, Keith M. Henderson

Lone Star Industries, Inc. in Cape Girardeau, Missouri operates an open pit mine to produce limestone for its portland cement manufacturing plant. The present mining method, for safety and legal reasons, requires a set back from the property line, a berm, sloped overburden, and vertical rock walls with catch benches.

Jan 1, 1997

By Tom Short

The contract to drive twin 4,100 foot (1250.5m) long tunnels under the existing Cumberland Gap highway was awarded to a Joint Venture of S.A. Healy of Chicago, Illinois and Lodigiani USA of Fairfax, Virginia in January of 1991 under a $51.8 million bid. Due to very complex geological conditions, there were six distinct categories of excavation, the New Austrian Method of ground support was utilized throughout.

Jan 1, 1993

By D P. Onag, B Mohanty

AECL Research (AECL) has constructed an Underground Research Laboratory (URL) as a facility for research and development in the Canadian Nuclear Fuel Waste Management Program. The objectives of the program are to develop and evaluate the technology to ensure safe, permanent disposal of Canada's nuclear fuel waste. Several multidisciplinary experiments and engineering demonstrations are planned for the URL over the next ten years.

Jan 1, 1991

By G E. Exedaktylos, Y Zhou

The complex and non-linear nature of blast fracturing has restricted common bract design primarily to empirical approaches. The code developed for this investigation simulates the pattern of interacting radial fractures from an array of blastholes, at various burdens and spacings, and in simultaneous and delayed modes. The resultant pattern is analyzed and a fragment adze distribution calculated.

Jan 1, 1989

By Roger L. Keller

This paper examines the aspects of differing types of blasting cuts in underground headings with consideration to the reduction of number of holes and costs. At least one comparison study is related where costs per advance meter were significantly improved. The technical aspect of the paper covers a study of the effects of various blasthole delay intervals on resulting crater volume, ground vibration, and fragmentation for six hole V-cuts.

Jan 1, 1989

By Gerald R. Coonan

Early in the open session of the 1979 SEE Fifth Conference panel discussion, someone asked a question of the panel concerning the future intent of the Office of Surface Mining and the regulatory limits established for ground vibration and air blast. The "gist" of the question was: "What assurances do we have that OSM will not promulgate a limit of 0.5 inch per second ground vibration, or some other number within the next two years or so."

Jan 1, 1979

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 Philip Barnhard, Lyman G. Bahr

By recording the arrival time of a pipe wall at evenly spaced intervals in a plane perpendicular to the pipe axis, application of the equations of motion permits calculation of the pressure of the explosive acting to accelerate the pipe wall. Data observed from various non-ideal explosives are presented, together with values of pressure to be expected from thermodynamic calculations.

Jan 1, 1981

By Dale S. Preece, J Paul Tidman, Stephen H. Chung

A discrete element computer program named DMC_BLAST (Distinct Motion Code) has been under development since 1987 for modeling rock blasting (Preece & Taylor, 1989). This program employs explicit time integration and uses spherical or cylindrical elements that are represented as circles in 2-D. DMC_BLAST calculations compare favorably with data from actual bench blasts (Preece et al, 1993).

Jan 1, 1997

By Abdel Rahman, M. Khaled, Abo Makarem

There are four large limestone quarries, located nearby Cairo metropolitan. Drilling and blasting operations are used to extract limestone for the cement industries. In these quarries, the blast vibration should be kept below a certain limit. One of these quarries is Tourah Portland Cement Company (TPCC) limestone quarry which, lies near important and historical large caves, within Tourah Mountain. Therefore, control of blast vibration level becomes very critical.

Jan 1, 2007

By John Turner, James Lamb

The Minnesota Department of Transportation (MNDOT) has an extensive project to improve driving conditions and reduce hazards to motorists on US Highway 61 between Duluth, MN, and Canada along the north shore of Lake Superior. In 1991, the Lafayette Bluff Tunnel was completed just north of Two Harbors, MN, through a joint venture of Johnson Brothers Corporation of Litchfield, MN, and Obayashi Corporation of San Francisco, CA.

Jan 1, 1994

By Tom Short, Bill Beam

Some of the weapons testing shafts at Mercury, Nevada require depths of 1000ft and diameters of 10 feet. The top 40 feet to 65 feet is drilled, blasted and excavated by Large caisson type augers in order to provide vertical working room for the placement of large, oil field type, drilling rigs and the required drill collar.

Jan 1, 1991

By Hans Florin

This paper describes the modification of a nonelectric detonator which is ignited by a signal tubing. The heart of the new detonator lies in a so-called ignition transmitting element. The construction of the transmitting element is such that the detonator remains closed even after the signal tube has functioned. Due to the sealing of the delay element, this nonelectric detonator achieves the same accurate delay timing as high tech delay electric detonators and will not fail due to a sudden pressure loss.

Jan 1, 1988

By Jerome S. Brower

Quadrex-L is a two component liquid explosive which was developed by J. S. Brower & Associates, Inc. to facilitate handling and shipping, and use in unique applications, while emphasizing safety. It may be advantageously used for all explosive applications. Quadrex-L can be introduced into a preinstalled container configuration and may be easily drained or flushed from these containers when necessary to do so. This characteristic can be effectively utilized to reduce the hazard period during assembly or disassembly operations.

Jan 1, 1975

By David Davison, Richard Johnson

Metal-oxidant blends are ordinarily unsuitable as diiect replacements for explosives, because the reaction occurs too slowly. Oxide coatings protect metals, preventing or delaying reaction. By contrast, the electrically-activated reactive composites described below are configured as metal fibers or foils in close proximity to oxidants, with continuous electrical paths from one end to the other. By quickly vaporizing the metal component with an electrical pulse, a reactive composite will be activated, and the reaction will occur rapidly.

Jan 1, 1999

By Scott E. Winston, Spencer C. Watson

Dynamite is a generic term for a variety of high explosive formulations containing a blend of liquid and solid nitrate esters co-mixed with solid oxidizers and carbonaceous fuels. Dynamites can be divided into general classes of nongelatins, semi-gelatins, and gelatins which vary as to their detonation rates, densities, and water resistance. There are also numerous products within each classification depending on their utilization or on their permissibility in various types of underground mining operations.

Jan 1, 1985

By Edward J. Walter

An ancillary effect to every blasting operation is the generation of vibration Extensive research has been performed for the purpose of understanding, controlling, and predicting this vibration An examination of these studies clearly shows a variability in the resulting vibration effects It seems logical to expect that identical blasting procedures should produce identical vibration levels, but this is rarely the case. There is a distinct pattern of variation.

Jan 1, 1980

By Walter Jr Duke

The security of explosive materials is a vital concern to every mine, quarry and contractor engaged in blasting. Proper construction of magazines and sufficient locking mechanisms are the fundamental means of maintaining secure storage. The object of this paper is to review the proper methods of construction of storage facilities for explosives as defined by the Alcohol, Tobacco, and Firearms regulations. Subpart K subsection 55.208 and the Institute of Makers of Explosives recommendations.

Jan 1, 1991