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By D. Goodings, W. L. Fourney, Bonenberger, R., Uli Leiste

The Dynamics Effects Laboratory at the University of Maryland conducted a series of very small scale tests to measure the impulse delivered to a plate by the detonation of an explosive charge which was buried in saturated sand. These tests were conducted to support a full scale tests series being supported by the Navy (NSWC Indian Head Division) to learn more about loads applied to structures by explosive detonation. For each of the tests being predicted, a series of three tests were conducted at Maryland, one with a 0.203 gm charge, one with a .609 gm charge, and one with a 3.3 gm charge. A high speed digital camera (500 frames per second) was used to record the displacement of the plate as a function of time. From this the initial velocity of the plate was determined and then the impulse delivered to the plate by the explosive. A best fit line through the data was determined for the three model tests conducted and this equation was used to extrapolate the predicted impulse for the full scale tests.

Jan 1, 2005

By Lawrence Mirabelli, Wayne Lidkea, Mario Paventi

On Januarv 1, 1996, INCO Limited, Tamrock OY, Dyno Nobel and CANMET formed a consortium for the development of robotic mining equipment called the Mining Automation Program (MAP). This project was a tive- [5] year research and development program that combined the talents of the above organizations to facilitate the development of mining equipment and systems for tele-remote mining. The year 2000 brings MAP to conclusion with actual production process trial testing of the developed prototype equipment and systems during the period between May and October. MAP consisted of multiple projects all of which are based on the communication system developed by INCO Mines Research and currently sold and marketed by Automated Mining Systems Limited. The main projects include the development of a positioning and navigation module (including a software mapping system that will be inherent to each piece of equipment), robotic systems for underground development and stoping operations, as well as software systems to support the use of this equipment. Included in the program was the establishment of a Research Mine, at INCO’s 175 orebody, Copper Cliff, Ontario, Canada. This facility allowed for the on-site collaboration between the companies and research organization in the design and testing of techniques and equipment to mine with TeleminingTM. Some of the prototype equipment developed through the program are: a tele-operated drilling jumbo, a tele-operated load-haul-and-dump [LHD] tram, a tele-operated production drill, a remote initiation system for programming and detonation of electronic detonators, and the development of a vatiable energy bulk emulsion explosive system, including loading equipment, to deliver the explosives to boreholes. Use of tele-operated and automated equipment for mining mandates a dramatic change in the traditional drill/blast/muck/support cycles in the underground mining process.

Jan 1, 2001

Jan 1, 2002

By S. P. Singh, Turgut Yalcin

The physical characteristics of blasted rock are fundamental variables affecting the economics of mining operations and are in fact the basis for evaluating the quality of a blast. A study was designed with the objective of quantifying the effect of muck size distribution on scooping operations in a mine.

Jan 1, 2002

By J R. "Dick" Daniel

In the fall of 1988, The Cannon mine decided to investigate a central blasting system based on conventional electric blasting detonators being used to initiate rounds primed with Nonel detonators. The advantages of this hybrid detonator system were viewed as being safety and cost effectiveness. A study was done reviewing the safety aspects of utilizing a permanent blasting line installed throughout the main haulage drifts to a central blasting station located at the mine portal. The study addressed the following potential safety hazards: radio frequency induced current, stray current from both electrical utilities and transmission lines, galvanic and electrostatic sources of extraneous current.

Jan 1, 1989

The reformulation of military explosives and solid propellants into commercial explosives offers a unique solution to the problem of disposing of high energy materials with essentially zero environmental impact at a low cost and with a salable product. Studies using the insensitive PBX PBXN-4 have been completed through the pilot plant stage and have been successfully tested as a mining explosive. A number of other military explosives have been examined and their VODs and heats of explosions determined and in some instances tested in 'field" operations.

Jan 1, 1995

By Cam B. Grundstrom

This paper will describe blast design modifications that have been made at the Island Copper Mine, near Port Hardy, British Columbia. To date, two additional designs have been implemented in an effort to reduce final wall damage and increase productivity. The typical blast patterns in use at Island Copper were monitored in an effort to build up data to which new designs could be compared.

Jan 1, 1994

By Josh Campbell

Modern blast engineering involves the use of modern technology to provide more efficient blasts. Through the use of improved measurement techniques more information can be obtained on many of the physical variables of a quarry rock face. By employing this information, a more efficient production shot can be designed and loaded. Along with improvements in production, greater safety and improved environmental impact can be achieved. This paper concerns the employment of modern blast engineering at a granite quarry in the Southeastern United States. The test period extended over a period of approximately six months, and this paper will show the results achieved in that time span.

Jan 1, 1998

By Paul Worsey, Gillian Worsey

Description of Project:The basic blasting class underground lab at the Missouri S&T experimental mine in Rolla, o., shows the students how to drill, set up, load, and shoot a shot underground. In this case the shot was part of a new ramp to a second level.

Jan 1, 2014

By Phil N. Bradbury

"During a routine belt tightening of all cost centers, the management at the Martin County Coal Surface Mines, located in Martin County Kentucky felt that a thorough investigation of the drilling and blasting program could possibly pinpoint areas where the cost could be cut without sacrificing production. Upon close inspection of the drill benches it was noted that the actual layout of burden,spacing and stemming varied a bit from the actual blast design that the management had outlined for the blasters. This paper will outline the method of reducing the drilling and blasting cost at the Martin County Coal Operation."

Jan 1, 1986

By Mike McGill, Steven P. Case, Mark Spaulding

The General Crushed Stone Company at Doswell VA. decided to open a new pit to expand their reserves. The elevation of the property was 136 feet above the present primary crusher. The project required driving twin tunnels under the highway to access the primary crusher from the new property. A shaft was needed to pass blasted rock to the tunnel elevation where it's loaded and hauled to the primary crusher. In addition, a ventilation shaft was required to provide adequate airflow. Dynatec Mining Contractors Inc. Lakewood Colorado was subcontracted to handle the tunnel and shaft development.

Jan 1, 1993

By Thomas P. Dowling

Since the 1950's, blasting practices have undergone many revolutionary changes. Some of the more radical departures have involved, in addition to high speed drilling equipment, a myriad of new explosives, blasting agents, boosters, initiators, initiating systems and delay devices. The introduction of ANFO in the mid 1950's as a blasting agent seems to have instigated a trend toward the development and use of less sensitive blasting agents. The evolution of slurries or water gels has produced dense, high strength, water resistant products which has further promoted this trend away from the more sensitive, conventional explosives.

Jan 1, 1975

I am interested in experiences people have had with blasting near existing railroad tracks: What kind of vibration criteria are used, and how successful you have been in gaining approval for blasting in the vicinity of railroads. This would both be for passenger and freight railroads

Jan 1, 2008

By Cam Thomas

"Reflectorless laser survey equipment has made it much easier to take accurate measurements toinaccessible locations in quarries, open pit mines and rock slopes. Prior to the introduction of thereflectorless laser as a working tool, it was not possible to directly measure to inaccessible locations on rock faces. If a person could not occupy the point, only indirect measurements could be made. For blasting work, measuring the burden in front of the first row of holes could only be done approximately, using such techniques as holding a plumb line in over the crest, triangulating in on a few points or “eyeballing” the burden. This led to direct and significant problems with blasting, including flyrock and airblast (caused by insufficient front row burden), excessive vibrations, problems with oversize and tight digging (all of which may be caused by excessive front row burdens)."

Jan 1, 1999

By Rolf Koenig

A fire aboard a vessel transporting explosives and detonators manufactured by Dynamit Nobel endangered the cargo. Due to the special safety properties of the detonators, no mass detonation occurred.

Jan 1, 1989

By John Wright

As part of the redevelopment of the Royal Brisbane Hospital complex in Australia, a number of antiquated buildings were to be demolished and replaced by newer, modem facilities. Aside from the decommissioning of the hospital buildings, the project called for the removal of approximateIy 24,000 bank cubic metres (bcm) of varying quality rock material. Given the sensitivity of the project, in particular the close proximity of the required excavation to the existing hospital structures (-3 metres at the closest point), and the requirement that these were to remain lily operational during the construction phase, it was initially proposed to use hydraulic rock hammers as the primary means of excavation. Poor production rates and unexpected dif3icuIt rock conditions led to a revision of the excavation methods and a feasibility study on drill and blast practices was undertaken. Subsequent to an initial series of trial blasts to illustrate that vibration and flyrock could be adequately controlled, drill and blast methods were used in conjunction with mechanical methods of rock breakage. This paper reviews the drU and blast processes and the practices which were necessary to comply with the multiple constraints imposed on the project. The project has highlighted that modified drill and blast practices remain a cost-effective method of excavation, even in sensitive areas which are commonly deemed inappropriate for such methods.

Jan 1, 2000

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 Ralph King

Blasting has been completed when the lawyer calls to say that a landowner has filed a suit alleging damages to the roof of his home. Mitigation talks fail to produce an adequate resolution and the case goes to court. The blaster has pictures of the area made after the blasting was done showing the good condition of the roof. However the judge fails to allow the photographs to be entered as evidence and the homeowner wins the case.

Jan 1, 2008

By Dean E. Albon

The author gives a brief resume of his observations of drilling and blasting supervision in surface coal mines during the past thirty years and recommendations for upgrading this supervision to the category of a professional.

Jan 1, 1979

By Alan R. Cameron, William W. Forsyth, Tom H. Kleine

In the production environment, the current limits of blasting are most often defined by the ability of the operator to drill blastholes from a planned collar location to the required toe location. Many problems which are initially described as deficiencies in blasting or support are directly related to drilling. The assessment of support performance and blasting efficiency must begin with a detailed examination of drilling practices.

Jan 1, 1995