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By R M. Bhatawdekar, A I. Theresraj, H S. Venkatesh

Wadi Limestone Quarry is one of the largest captive mines of Associated Cement Companies Ltd, India. The mine management wanted to extend the excavation as close to the plant as possible for maximum exploitation of the deposit. The National Institute of Rock Mechanics and the management of Wadi Limestone Quarry carried out comprehensive investigations to evolve a methodology to control vibration and flyrock within safe limits.

Jan 1, 1999

By Thomas L. Barkley

This paper describes an unusual design for a 12 foot diameter, 30 foot deep circular shaft shot in a close in urban environment less than 100 feet from occupied structures. It uses diagrams, video footage, and vibration results to describe a 3 deck, 17 hole burn round used to pull 17 feet in one lift.

Jan 1, 1994

By Thomas E. Brown

With the ever increasing public sensitivity to our environment, the blasting industry can no longer be concerned with just drilling and blasting. Government regulations, augmented by public pressure, require that the industry must be more diligent in preventing spills, disposing of distressed products and packaging materials, controlling fumes and dust, preventing product contamination, developing environmental impact studies, and preventing unnecessary regulations. These liabilities in conjunction with those of vibration, air overpressure and flyrock will continue to greatly impact the industry.

Jan 1, 1995

By Jeff Hermanson

Every construction project has site specific problems that need to be dealt with. These problems may be created by the geology, location, weather, time constraints, etc. Once these problems have been solved their solution often can be transferred to other similar construction sites. The Crazy Horse Memorial project is no exception.

Jan 1, 1996

By Richard B. O'Meara

"The demand by a customer to an Explosives supplier to fulfill a specialised productrequirement was met by a level headed decision to try to satisfy that demand. This paperwill describe the fundamental steps required in order to develop and produce a newexplosives device, while under certain resource constraints, such that the needs of thecustomer and the supplier are met safely and effectively."

Jan 1, 1993

By T N. Hagan

Where explosion energy moves rock from the in-situ to its desired location without considerable assistance from digging and/or hauling equipment, good fragmentation is of minor importance. Maximum displacement must remain uppermost in the mind of the blast design engineer.

Jan 1, 1979

By Jack Elorenta

A recent forum of mine operators revealed a continuing strong interest in alternative methods of freeing rock. A Rand Corporation report lists a continuous mechanical machine that would replace drilling and blasting as a priority for mine operators. Meanwhile, mounting evidence documents a dramatic cost benefit in processing where increased blast energy is available. The reasons for this dichotomy may be due to a number of factors.

Jan 1, 2002

By Mauro Fornaro, Marilena Cardu, Renato Mancini, Daniele Castano

Tunneling by explosive blasting in civil works isn't merely intended to break somehow a way through the rock, rather to drive a permanent, constant cross section, lined way. The current mechanical excavation v/explosive blasting debate is mainly centered on the concept of the tunnel wall quality; and consequently explosive blasting strategy is founded on contour blasting.

Jan 1, 1992

By William D. Hissem

The purpose of this paper is to advise people about the methods, use, and possible applications of current "personal computer" hardware and software with regard to the economic cost analysis of percussion drilling equipment. The material content and orientation of this paper is toward those people who have just begun "PC" (personal computer) operations, and (or) those who are considering their use.

Jan 1, 1986

By Bruce B. Redpath

This paper reviews empirical and analytical information about window breakage due to airblast. As is the case with damage to structures caused by ground vibrations, a fixed break/no break threshold is inapplicable and window damage must be expressed in terms of a statistical probability. The information is summarized in a graph showing the probability of windows being broken by a given level of overpressure.

Jan 1, 1976

By Stephen Hamilton

This case history details the issues surrounding the rock drilling industry’s growing demand for straight holes, the importance of straight holes and the introduction of a new production drilling systems that can effectively and economically drill a true bore hole. Since the introduction of the hydraulic rock drill, the rock drilling industry has asked for a drilling system that would provide the fast penetration and low operating costs of Top Hammer drilling systems combined, with the directional control of Tube or DTH drilling techniques.

Jan 1, 1999

By Fumihiko Sumiya, Koichi Kurokawa, Yukio Kato, Tetsuya Sawada

In some metal mines, it is a serious problem the decomposition of explosives which occurs suddenly by contact with ore containing pyrites under high temperature conditions. In the present paper, we investigated heat resistant properties of emulsion explosives and other industrial explosives by contact with ore containing pyrites under high temperature conditions.

Jan 1, 1992

By Richard L. Ash, Calvin J. Konya

Proper selection of the spacing distance between blastholes is fundamental to successful blasting. Its value directly affects the profitability of an operation. It also exercises control over adverse effects such as airblast, flyrock, generation of ground vibrations, and overbreak. One of the more significant factors influencing the spacing's specific value is the initiation firing time intervals used between blastholes. Examples are described to illustrate some of the problems that result when spacing and timing are not compatible.

Jan 1, 1979

By Jay P. Tobin

This paper will address the legal standards applicable to construction blasting lawsuits and offer best practices suggestions for pre-blast inspections, documenting the construction blasting work, recordkeeping, and effectively participating and partnering in the defense of a construction blasting lawsuit.

Jan 1, 2015

By Tom Donnelly, Roger C. Ilsley

Remote telecommunications seismographs were used to monitor blast vibrations at two historic structures in Cedarburg, Wisconsin during adjacent sewer line construction. The purpose of the vibration monitoring program at the historic structures was to maintain blast vibrations below limiting tolerances established by the Wisconsin State Historic Society.

Jan 1, 1991

By John F. Vynne

This paper will discuss the application of available monitoring technology on blasthole drills with the goal being to reduce costs and increase productivity. Case studies from the monitoring of blasthole drills in North American open pit mines will be used to illustrate the ability to meet these objectives.

Jan 1, 1997

By He Guangyi

During rock blasting in extending deep cutting from Jiu Li Mountain to Dong Zhuang Village in Jiao Zhi Railway line, we have drilled deep hole with large scale diving drilling machine and successfully carried on controlled blasting. This has provided new experiences for rock blasting in extending existing cutting. The aim of this article is to provide an introduction to bench height, blast holes arrangement, powder charge calculation, and detonating technique during blasting.

Jan 1, 1997

By C Jamie Kridler

"An increased concern for pit safety and more stringent, highwall requirements for augermining of final cuts has led to a new emphasis on wall control for a Central Pennsylvaniacoal operator. Over the course of two and one half years and several locations, fieldpersonnel developed a very practical yet very effective system for maintaining safehighwalls. This involved the use of the blast design to: l) shape the highwalls 2) create andprotect a system of benching 3) pre_split large diameter holes using suspended ANFOcharges."

Jan 1, 1993

By R J. Roach, D Roy

After months of discussion on ways and means to improve productivity in the shaft sinking process, it was decided to look at those areas where, historically, methods have been stagnant for many years. These categories included drilling, hole diameter, drill patterns, explosive types, explosive loads, initiation techniques, cut design, wall control, fragmentation and heated magazines.

Jan 1, 1997

By Lawrence Cheng-Kwang Hu

"Since the only available delay detonator in Taiwan is electric delay detonator, which can beaccidentally initiated by fire, i impact force, friction, static electric, lighting, radiotransmitter, and stray current etc., that always represent fatal threatens to the blasting crew.Fire, impact, friction can be Prevented by handling carefully; lighting also can be detectedwith proper instruments. But when a blaster find an unknown extraneous current in his welllaid down blasting cable; what a horror scence will be expected especially the electricdetonators have been connected already."

Jan 1, 1993