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By Michail G. Egorov

As well as destruction and moving rock, the blast energy sets up a seismic wave in the ground and a shock wave in the air, which can present danger to buildings and disturbance to human occupants. This shock air wave potentially can cause to destruction of a window glass, the window and door frames and partitions of buildings. In modern buildings, distinguished with high flexibility, the shock air wave can cause to the intensive wall vibration, dangerous for these buildings.

Jan 1, 1996

By Karl E. Burgher

Accidental explosions occur throughout the world. They can happen at chemical plants, fireworks plants, grain depots, or as a result of collisions involving volatile or hazardous chemicals. It is interesting, as we know as blasters, that we can take two very harmless products and mix them under certain conditions and produce a violent explosion. It is often very difficult for the investigator to determine the magnitudes of blasts after the fact. However, an estimate must be made to settle vibration and airblast damage claims. The blasting consultant or technical representative is often called upon to act as an expert to mitigate these claims.

Jan 1, 1993

By James E. Jr Hargroves

With the ever-increasing population growth and modern trend to urban development, the expansion of utilities is a stable, mad or, and constant source of income for many. Blasting is a "necessary evil" to the utility contractor. It can make or break even the most solvent. Housing development expansion and higher treatment of effluents are causing utilities to appear in more congested areas. This paper discusses some of the aspects of utility blasting in the State of Virginia. Consideration is given to bid procedures, pre-blast surveys, record-keeping and practical application.

Jan 1, 1977

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 James W. Reil, Douglas A. Anderson

Common wisdom has it that a blast which breaks rock efficiently should-generate less ground vibration. In practice, however, this idea has not been-rigorously tested. In a previous paper presented at an SEE meeting[1] we described a method for-controlling vibration using delays. The method is very effective in controlling-annoying low-frequency ground vibration. We noted that observed ground-vibration differs in some respects from that predicted by adding single-charge-waveforms.

Jan 1, 1988

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 William C. Geitz, Dan Fitzgibbon

Lightning has always posed a serious threat to blasting operations, especially within the mining and construction industries. In recent years, technological advancements in communications systems and microprocessors have significantly improved the accuracy and efficiency of lightning detection and warning instrumentation. These advancements have increased the availability of highly reliable, accurate and affordable systems for use within the explosives arena.

Jan 1, 1991

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 Kamal Wadhwa

Liquid oxygen explosives have been used in India for well over 5 decades now. These are being extensively used both for shallow and deep hole blasting in the various opencast mines and quarries for mining of coal, limestone, ironore, bauxite, magnesite etc. IOL Ltd., are the pioneers in the introduction of these explosives in India and are marketing these under the brand name 'LOXITE'.

Jan 1, 1991

By G Dean Barrett, Ed Jr Smith, Calvin J. Konya

The purpose of the project was two fold: 1. To determine whether Pyrodex, a propellant, manufactured by the Hodgdon Powder Company, could be used as a substitute for high explosives for presplitting in granite and other materials. 2. To determine if Pyrodex, a slow reacting propellant which produces no stress waves in rock because it reacts subsonically, could cause the rock to crack similar to the results achieved with high explosives.

Jan 1, 1986

By Wang Xuguang Shen Yingfeng

Structure is the main aspect affecting the performance of emulsion explosive. Calculation of such structure parameters as osmosis pressure, interface area per unit volume etc. must be helpful to the understanding of the structure of emulsion explosive. This paper has solved the Laplace-Young Equation for simplified monodisperse emulsion system by Galerkin method, and gained the relationship between mean curvature, contact angle, volume fraction, fractional film area and interface area per unit volume. The paper also presents a new expression of osmosis pressure at non zero contact angle.

Jan 1, 1998

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 Baron Fidler, Dave Lilly, Matt Budin

Cumulative sum (CUSUM) statistical process control methods have been used in many industries to monitor quality control results. CUSUM charts are a method to determine when small changes in data indicate a major change in results. E.S. Page at AT&T developed the method in 1954. In many blasting situations, vibration and air blast readings vary slightly from blast to blast. Whether the change is significant or not can be hard to interpret from the raw data. CUSUM charts can assist in determining whether a major change is taking place and when the change began.

Jan 1, 2009

By S B. Richardson, N T. Moxon, A C. Torrance

In many mining situations the energy released by an explosive is far too high and results in over fragmentation and excessive damage to the surrounding strata. Laboratory experiments have demonstrated that the shock energy of an explosive can be significantly reduced by surrounding it with an attenuating material such as a foam. The effect of this reduction in shock energy on fragmentation has been determined using model materials. A four fold reduction in the amount of minus 8mm material relative to an air decoupled charge of the same weight was obtained for a foam attenuator.

Jan 1, 1989

By Sharon K. Reamer, Yvan Sifre, Klaus-Gunter Hinzen

"Three case studies are presented that illustrate the successful application of firing timeoptimization (hybrid modeling) in the quarry environment and for a construction site. In allcases, the method requires the measurement of at least one in situ, single hole explosion asa representative model of the desired blast design."

Jan 1, 1993

By Charles A. Kliche

The Comprehensive Environmental Response, Compensation and Liability Act of 1980 (CERCLA) established a national program for responding to releases of hazardous substances into the environment. The funding mechanism for this program is the Hazardous Substance Response Trust Fund (commonly referred to as Superfund), which provides funding for the implementation of removal and remedial response actions.

Jan 1, 1997

By Scott Giltner, Allan Koski

Blasting is one of the lowest cost yet most critical parts of the mining cycle. This paper discusses the findings of an audit conducted on the blasting operation at an iron ore mine. The purpose of the audit was to review current blasting practices in order to identify opportunities for production/cost improvements. The approach taken in the audit was to observe general blasting practices, their related downstream effects and to compare current procedures to established best practices.

Jan 1, 2009

By Syed M. Tariq, Paul N. Worsey

Pre-splitting is now widely used to minimize overbreak and to protect final surface rock excavation profiles in large scale civil construction projects, open pit mining and quarrying. Jointing has been shown to affect the success of pre-splitting and the smoothness and integrity of the resulting rock face. Many facets of jointing have been investigated in detail, including the inclination of joints with respect to the desired pre-split plane, the effects of various filling materials, etc. However, the effects of joint frequency and spatial positioning has been paid little attention. The paper addresses this issue.

Jan 1, 1995

By Paul Worsey, Larry Kenchel, David Randall, Mark Schmidt

The University of Missouri-Rolla (UMR) has historically maintained a manual, paper inventory of explosives stored and used at the university. Although this system was accurate for inventory control and reporting criteria, it was labor intense and delays in record keeping were predominant. A directive from the university’s administration mandated the development of a precise real time system “on-line” to maintain and control the explosives inventory in line with the universities new chemical tracking policies.

Jan 1, 2001

By L D. Lawrence, W B. Sudweeks, J Bailey

Modern era urbanization is presenting at least one category of explosive consumers with a growing concern for ecological and environmental problems associated with their blasting processes. The construction industry is now, more than ever, being closely monitored with regard to its use of high explosives. In particular, contractors excavating the countless thousands of miles of various trench lines required for virtually every major new construction development taking place in America are being more closely scrutinized by local, state, and federal authorities with regard to blasting practices.

Jan 1, 1988