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By Tapan Goswami, Geoff Keith

"At Bulga Coal, the objectives of drilling and blasting are to maximise safety and to minimise the totalcost of mining. A recent audit of two overburden blasts established that the standard of drilling and blasting is excellent. No apparent hazards were identified. Laser profiling showed that highwall free faces are reasonably planar with some exceptions, thereby promoting uniform burden distances along front-row charges. However, in three isolated areas along one face, small burden distances existed. The mean and the standard deviation of errors in the collar positions of front-row blastholes was found to be 0.3 + 0.03 m. A borehole video camera was used to show that blastholes did not feature open bedding plane partings, cavities or damage produced by the blast in front of them."

Jan 1, 1999

By Quian Liu

Since the establishment of the CANMET Experimental Mine in Val d'Or, Quebec in 1991, research activities in rock fragmentation have been carried out not only in the underground laboratory but also in production mines in the north-west Quebec region. Among the instruments available for rock fragmentation, the Kodak EktaPro 1000 Motion Analyzer (also called the high speed video system) has been one of the most useful tools for monitoring blasts in both underground and open pit. This system is capable of recording events at rates from 50 to 12,000 frames per second (fps). The buffer memory has a capacity of storing 2050 images. To use this system in the underground, a steel box was made with a bullet-proof glass in the front to protect the camera. The processing and recording equipment are placed in an aluminum case which can be located about 30 m away from the camera via an extension cable. For each blast monitored, high frequency geophones and accelerometers were used to monitor ground vibrations and give a timing reference of the explosive detonations to correlate with the observation of the captured images.

Jan 1, 1994

By Doug Wathen, Philip M. E Thomas

The City of Fort Myers needed to replace a 40-year old 42-inch storm sewer line in downtown Fort Myers with a new 54-inch line to accommodate population growth. The old line had to be kept operational while a new line was installed. The contractor spent two months using a drop ball, a hoe ram, and large rippers trying to break the three to four feet of rock that needed to be removed to accmmodate the new pipe. Mechanical trenching was considered but was proven to be overly expensive. On very short notice, Ireco of Florida was asked to design and execute a blasting procedure that would allow this project to proceed. Nearby buildings were over 80 years old, three of them containing antique shops specializing in glass antiquities with attorney offices above them. High water table compounded problem with a 20-year old steel water main and clay drainage pipe 15 feet frcan the new sewer line. Holes had to be drilled within six inches of the edge of the existing pipe to four feet below the pipe on either side of the pipe and blasted. No interruption in the sewer line flow was to be tolerated.

Jan 1, 1996

By William F. Skully

An effective explosives storage program involves selection of a storage site, checking zoning and special permit requirements, acquisition of the storage site land, determining correct layout for required storage units, selection of storage units, construction of storage area, obtaining licenses and permits, and storage site operation.

Jan 1, 1976

By N H. Maerz

The digital image analysis program WipFrag has been developed under contract to INCO for use in quality control of underground blasting operations. This paper outlines the relevance of fragmentation to underground mining, the hardware and photography requirements, and key features and operating principles of the software.

Jan 1, 1995

By A N: Zditovetsky Shishov, M G. Menzhulin

At present in a building industry demand for products from granite, gabbro and other rocks, steady to erosion, natural and chemical weathering, was essentially increased. It has caused the enlargement of exploitation of stone block deposits and necessity of creation of new technologies of hard stone cut.

Jan 1, 1996

By M Dale White

In December at the Commonwealth of Kentucky Fifth Annual Blasting Conference of the Division of Explosives and Blasting, Department of Mines and Minerals, I delivered a paper entitled "Problems on Blasting Insurance. " Donald H. Matthews, President of Explosives Engineers, Inc. located in Sparks, Maryland came up to me before the program and said, "We explosives users know what the problems are. What we need is someone who can solve those problems. "

Jan 1, 1979

By Erik Nygaard

During the last years, ammonium nitrate has been involved in several accidents worldwide. This have caused increased focus on security and safety issues and resulted in:• Revised Yara standards • Revised international standards for storage and transportation • Stricter regulations from national authorities in many countries.

Jan 1, 2008

By Michael S. Stern, Gordon P. McDonald

The increasing costs and problems associated with transporting and safely disposing of used engine oils from remote mine sites have caused mining companies to consider other ways to consume their used oil. One practical method of disposing of these used oils is to blend them with the diesel component of ANFO and Heavy ANFO type explosives.

Jan 1, 1993

By N K. Jain

"The idea of writing this article is to give correct picture about the technique in blastingindustries based on the safety aspect, basically without effecting the results thereof.Like many other sciences, blasting is rapidly advancing and research scientists are dailycreating new devices which are very reliable and efficient.The theory of explosion and all the respective changes caused by the explosives takingplace during the detonation has been brought up to the level enabling a mathematicalexpression of detonation characteristics even in comparative complex cases."

Jan 1, 1993

By Jeffrey E. Loney, Andrew F. McKnown

Recovery of contaminated groundwater migrating through bedrock can be very difficult due to the low transmissivity of many bedrock fracture systems. To overcome these difficulties, a system of controlled "trench" blasting has been used on several projects to assist in cutting off and collecting groundwater plumes in bedrock. By using a combination of trench blasting and presplitting techniques, linear "fracture" zones are created in appropriate locations to significantly increase flow into recovery wells and control plume migration.

Jan 1, 1995

By K Ramachandra Rao

This paper explains the methodology for assessing the efficiency of rockmass fragmentation by explosive blasting, from ground vibration frequency spectrum analysis of the blast event. Explosives are used in the mining, quarrying and construction industries for fragmenting rockmass to a suitable size. When an explosive charge is detonated, in addition to fragmenting the rockmass, it will also generate ground vibration and air vibrations. Efficiency of a blast depend upon percentage of blast energy wasted in generating ground vibrations and air vibrations.

Jan 1, 1994

By Adrian J. Moore, Alan B. Richards, Rob Evans

Air and ground vibration from blasting is influenced by the delay pattern that is used. Wavefronts from blastholes fired in a blasting pattern can combine in certain circumstances to give increased blast vibration levels. A simple computer model has been developed which shows the combined effect of wavefronts from a multi-hole blast and identifies if wavefront reinforcement occurs, and permits delay patterns to be designed which will avoid or reduce wavefront reinforcement.

Jan 1, 1994

By Alfred Osborne

Progressive cavity type pumps are widely used by commercial explosive manufacturers for pumping water gel, emulsion and emulsion / ANFO blend explosives. Tests by explosives companies and investigations into incidents have shown that this type of pump can develop dangerously high temperatures when operated deadheaded or dry. [i.e. with no flow of product through the pump.] In some tests and incidents, explosion or detonation of the explosive (or residual explosive) in the pump has resulted.

Jan 1, 2002

By Tom Hanke, Joe Strobbe

The 80 year old Theodore Roosevelt Dam built in a scenic canyon near Globe, Arizona is currently undergoing a major renovation. The old stone dam, built by hundreds of skilled stonemasons, is being covered with a new concrete face that will increase the dam height by 77 feet. The renovated dam will improve flood control and provide increased electrical power and recreation area. The contractor, J.A. Jones is constructing the new dam and powerhouse for the Bureau of Reclamation.

Jan 1, 1993

By Alex Jankovich, Darren Thornton, Sarrna Kanchibotla, Cam Grundstrom

The Porgera joint venture and Dyno Noble have commissioned a joint project to optimise the drill and blast operations to increase the overall profitability of the mine. One of the aims of this project is to increase the throughput of semi autogenous (sag) mill by optimising the blast fragmentation, The work done so far clearly indicates that significant improvements in sag mill throughput can be achieved by optimizing the blast fragmentation. This paper discusses the planning, implementation and results achieved so far in this project.

Jan 1, 2001

By Don Thompson

The Minntac Mine drills and blasts approximately 75 million long tons of taconite per year. This requires drilling one million feet of 1 6-inch diameter holes. We are in the process of replacing our old generation rotary blasthole drills (Gardner-Denver 120's and Bucyrus-Erie 61R's) with new generation rotary blasthole drills (Bucyrus-Erie 59R's and P&H 120A's).

Jan 1, 1998

By Gungor Tuncer, Ali Kahriman, Abdulkadir Karadogan, Simav Bargu, Savas Gorgun, Derya Kucukbrtem, Esat Tansev

Although many research studies had been carried out in the past in order to eliminate environmental issues produced from blasting unfortunately a general approach or formula has not been established yet because of the complexity of the matter. In addition to the wave and ground motion characteristics, the complexity of blasting parameters and site factors restrict the developing of a general criterion. So experimental site-specific studies should be still done in order to predict and control blasting effects.

Jan 1, 2002

By R C. Berglund

Since the Republic Mine began production in the mid 1950's, drilling and blasting practices have continually changed. In recent years, progress has been achieved through the development of more precise blast engineering methods, in greatly increasing the use of non-water resistant ammonium nitrate explosives, and in changing to a non-electric in-hole delay initiation system. Also, recent experience indicates that ammonium nitrate fueled with nitropropane and methanol is a viable substitute for aluminized AN-FO.

Jan 1, 1980

By Neil E. Gehrig

The word "slurry" was used by Dr. Melvin Cook and Mr. Henry Farnam to describe a new blasting agent developed in 1956. This development, along with the development of ANFO triggered the Modern Era of Blasting. We have seen the results, a massive expansion in the commercial explosives industry. Someone once said, "You can't know where you're going if you don't know where you've been." With that in mind, this paper deals to some extent with the origin and development of slurry explosives and then with their future high potential.

Jan 1, 1982