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By I E. "Chip" Harris, G Alan Foster

Whilst a great deal of published data exists as to safe ground vibration and air blast levels which result from blasting little documented research has been carried out to determine how and why human beings complain about blasting operations. This paper gives the authors thoughts and experiences of why complaints arise and practical steps to minimize such complaints.

Jan 1, 1977

By T. Bajpayee, G. Mowrey, D. Ingram, T. Rehak

Blasting operations are an essential element in the recovery of our Nation’s mineral resources. The mining industry uses billions of pounds of explosives annually. The majority of blasting occurs in surface mining .operations. Blasting results in the fragmentation and often the projection of rocks. Frequently, the rocks are thrown beyond the expected limits. Flyrock and failure to secure the blasting area dominate blasting-related accidents in mining, especially in surface mining.

Jan 1, 2001

By Clifton W. Livingston

This paper is the first of a series in which evidence suggesting a quantum mechanical behavior of materials in blasting and high energy impact loading is presented. Such evidence relates the mechanical behavior of materials to their electro-magnetic behavior at successive stages in the development of the electric and magnetic fields as the disturbance proceeds outward from the borehole in blasting.

Jan 1, 1981

By Charles H. Dowding

This paper describes NUVIB, analytical software to digitize, analyze, display, and plot time histories generated by blasting and construction vibrations. It is available in conjunction with a new book on Construction Vibrations (Dowding, 1996) through internet procedures described at the end of the chapter on analytical software These internet based procedures eliminate the need for inclusion of disks in the book and take advantage of the growing electronic communications network. Perhaps more importantly this procedure allows the software to be updated more often than the book is reprinted.

Jan 1, 1997

By M Oldenburg, P J. Digby, L Nilsson

A constitutive model for the simulation of fracture and fragmentation processes in rapidly loaded rocks is studied. The model was included in a wave propagation finite element code. The results obtained from two different configurations of explosive charge and reflecting surfaces in a plane strain problem were studied. The evolution of the time-dependent fracture pattern is presented.

Jan 1, 1985

By Calvin J. Konya

There have been many different brands of high precision caps introduced on the US market in the last five years. High precision timing definitely effects the performance of the blast. One should be able to optimize fragmentation and minimize environmental effects with the use of high precision caps and selection of the proper time period. The consumer who purchases the caps may not be fully aware of the tolerances in firing times of caps used in the field. This paper will discuss results of field tests of cap tolerances from an independent study conducted by Precision Blasting Services.

Jan 1, 1989

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 Jeffrey N. Deisher, H Y. Fang, Richard P. Scheller, Robert M. Koerner

The need to adequately quantify cracking in structures in the vicinity of blasting activity becomes more important each year. This urgency comes about through a growing number of complaints and lawsuits between the various parties involved, i.e., operator/owner, government, and complaintant. It is felt that existing rules and regulations (mainly based on peak particle velocity of the soil or rock adjacent to the structure in question) fall short of such quantification and lead to confusion in adequately assessing structural damage.

Jan 1, 1977

By John M. Bolger, Keith E. McMaster

Excessive salt fines are undesirable in underground salt mining as they are considered a costly waste byproduct. This paper describes an extensive explosive application program conducted at The Canadian Salt Company Ltd, located in Pugwash, Nova Scotia, Canada. The prime objective of the program was to reduce the quantity of fines generated from this company’s underground production blasts. The program was known as the “The Fines Reduction Program”.

Jan 1, 1996

By Kenichiro Yamamoto, Masaharu Murakami, Toshio Matsuzawa, Yoshiyuki Ikeda

In a series of tests, we examined the dynamic shock resistance of Emulsion Explosive in water and compared it with that of Dynamite and Slurry Explosives. Both the distance between donor and acceptor charges and the delay initiation timing of the acceptor charges were varied. The resistance to dynamic shock varied with the properties of the explosive. In the case of emulsion explosives, there seems to be a certain proportional relationship between the critical detonation distance and the delay initiation timing. Some blasting results with emulsion explosives are described.

Jan 1, 1983

By G Dean Barrett

Just one year ago at the 1986 Annual Meeting of the Society of Explosives Engineers, Dr. Calvin J. Konya presented a paper entitled "Presplitting Granite Using Pyrodex, A Propellant.'' Since that time more evidence has been developed to support the concept that "...gas energy can be the principal splitting force and that the stress wave or shock wave is not necessary to cause the presplitting action to occur." Work done in Vermont and Georgia is presented, and the ability to split granite without causing radial cracking of the bore holes is demonstrated.

Jan 1, 1987

By Sarma Kanchibotla

In mineral industry operations the insitu ore is’separated from the waste rock and is subjected to a series ofprocesses to convert it into a valuable product. Profitability of any operation in this industry depends on how eficiently the insitu rock (ore -I- waste) is converted in to the final product and how much value @ice) it commands in the market. Traditionally, the total process in mineral industry is classt@ed into two groups as mining and milling, and optimised independently without considering the impact of one over the other. This paper investigates the impact of mining operations (especially blasting;) on downstream processes and demonstrates the potential benefits of the “Mine - Mill Blasting” approach through simulations and case histories.

Jan 1, 2000

By Brendan O'Reilly, Outokumpu Zinc, Geoff J. Johnston, S Durucan

Historically vibration monitoring has dealt primarily with surface blasting or "near field" monitoring of underground blasts. The Situation at Tara Mines is different, blasting occurs up to 400m underground, with a number of blasts occurring daily and occasionally with residential properties directly above the blasting site. Tara Mines, due to both its location (1.5 km from the rural town of Navan) and stringent planning conditions have always had to monitor, carefully plan and control the levels of vibration from blasting. The statutory vibration limit at Tara allows a maximum peak particle velocity of 7.62 mm/s with no frequency limitations. Levels of vibration have been monitored continuously since mining operations began in 1972.

Jan 1, 1994

By Raymond Hofstetter, Paul Worsey

The purpose of this paper is to investigate commonly used methods for mitigating the effects of shrapnel from linear shape charges (LSC) used in the demolition industry. Primarily the problem is not that shrapnel poses a threat to human bystanders, but rather it can affect the other charges in the demolition or damage to structures in close proximity to the charges. This research aims to determine what methods have success at stopping shrapnel, what methods do not, and to promote an awareness of the dangers of using the LSC without any protection. The project was carried out at the Experimental Mine site at the Missouri University of Science and Technology. This research is an undergraduate research project to fulfill the requirements for the Explosives Engineering minor program at MST.

Jan 1, 2008

By Otto E. Jr Crenwelge, Timothy A. Peterson

We have developed a site-specific method for analysis, prediction, and control of ground vibrations induced by overburden blasting operations in surface coal mines. Field tests conducted at R&F Coal Company have verified our approach for obtaining signatures of the overburden vibration characteristics at locations of interest near the mine, selecting the optimum excitation frequency for minimizing vibrations, measuring and synthesizing multiple-charge excitation signals for minimizing vibration amplitude and duration and controlling frequency, accurately predicting the multiple-charge vibration response in both the time and frequency domains, and accurately controlling the blast detonation to achieve the predicted vibration control. Initial field studies also indicate that by minimizing the vibrational energy radiated from the blast zone, and by optimizing the number of charges detonated per delay period as allowed by this technique, more effective use of the explosive energy is obtained within the blast zone itself for improving overburden fragmentation, swell, and cast. In all of the phases of this technique, including actual blast detonation, personal computer hardware and software have been verified for use in either field or office environments.

Jan 1, 1986

By Jack Eloranta

Building on previous work, this paper expands the template for modeling the economic relationship between blasting and grinding. The actual efficacy of various blasting enhancements is not addressed, however, placing costs and potential benefits in proper context should aid in designing mine/mill optimization trials.

Jan 1, 2014

By Park McLure, Paul Kunze

Abandoned underground mine workings have been regularly encountered in open pit mining excavations for many years, for the most part without many serious problems resulting. During the last several years however, some tragic occurrences and near misses have resulted when these old workings were intercepted. This paper will report on the problem as it relates to western open pit mining and will describe several techniques that can be used to identify problem areas before they are reached: Utilization of old maps and engineering data, long hole drilling and probing, and the use of subsurface investigation in the form of ground penetrating radar are the detection methods that will be discussed. The paper will describe some possible actions, once potential problem areas are identified. Drilling and blasting crews are usually exposed to the hazards involved when these situations arise because of their "on the ground" working environment. It is therefore appropriate that some of the best methods of dealing with these hazards once they are identified, seems to involve innovative and creative blast designs. The paper will discuss these approaches and describe an example of this aspect of the solution.

Jan 1, 1993

By Frank Lucca

This study is based on a six month study performed for Lee County, Florida. The study was based on blasting for land development and how this type of blasting affects structures. The study is investigates peak particle velocities and the relationship to other environmental and manmade forces that affect structures. The study also explores the effect of geology on blast vibration. After completion in Lee County, the study was then continued in the quarry environment in Vermont and extremely tight blasting environment of New York City. Charge diameters were 127mm (5 inches) or less.

Jan 1, 2006

By Robert L. Martin, Brian W. Stump, David P. Anderson, David Gross

In an attempt to better understand the impact that large mining shots will have on verifying compliance with the international, worldwide, Comprehensive Test Ban Treaty (CTBT, no nuclear explosion tests), a series of seismic and videographic experiments has been conducted during the past two years at the Black Thunder Coal Mine. Personnel from the mine and Los Alamos National Laboratory have cooperated closely to design and perform experiments to produce results with mutual benefit to both organizations. This paper will summarize our activities, highlighting the unique results of each.

Jan 1, 1997

By Kevin Cole, Dennis A. Clark, F William Laslow

Since 1976, the Metropolitan Sanitary District of Greater Chicago, (MSDGC), has commissioned the excavation of a tunnel system in the Chicago area, hundreds of feet below the surface in solid limestone. This paper outlines the blasting patterns, explosive selections, and monitoring techniques used to assure a satisfactory job completion, following the specifications.

Jan 1, 1982