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By Wang Xuguang, Kang Tingzhang, Zhang Xiaozhi, Wang Guoli, Li Ziqianga

Emulsion powder and granule explosive is produced through airflow fluidization technology by using W/O emulsion. Maintaining the microstructure of W/O emulsion, it has the advantages of both emulsion explosives, such as good water-resistance and detonation properties and powder explosives, such as low cost and east handling. The basic theory of emulsion powder and granular explosive, choices of constituents and formulation, technology for preparation, equipment and relevant parameters, product property as well as technology for safe use have been illustrated in this essay. Based on the above illustration, related factors influencing property and use result have been analyzed.

Jan 1, 2000

By Terry Graf, Bill Thompson, John Guenther

SYNCRUDE CANADA LTD.. operates the largest synthetic crude oil production facility in the world. Over 60,000,000 Bank Cubic Metres of oil sand is mined each year from their open pit located in Fort McMurray, Alberta. Despite the extremely cold temperatures encountered during the winter months and the problems associated with frost buildup, SYNCRUDE has continued to operate on a 12 month per year basis. In 1989 SYNCRUDE mine management embarked on a comprehensive Frost Blasting program to improve mine production of their oil sand moving equipment. The following paper will discuss the development of their frost blasting program to its current status.

Jan 1, 1993

By Jianjun Tang, Wenjuan Bai

This paper presents a new method of formulation design for multi-component composite explosives. Based on the thermochemistry of the detonation process, the mathematic model of formulation design is established by optimization mathematics. Using the heat of detonation as target functions and taking the constraint conditions such as oxygen balance and costs etc into consideration, this model can provide an optimal solution quickly by means of personal computer. Using this method, the calculation and the simulation tests for a series of constituent sets and various constraint conditions can be conducted easily. In this way, the optimal formulation for the explosive can be determined, on the basis of the maximum heat of detonation and the lower cost.

Jan 1, 1997

By Gregory P. Lorsbach

Significant information about any blast is contained within the seismic signal generated by the blast. In this study, standard digital signal processing techniques are utilized to extract source parameter information from a seismic signal recorded at distances commonly used in compliance monitoring. Specifically, digital seismic data was analyzed using the cross-correladon and autocorrelation functions for the purpose of determining delay timing. The initial results are interpreted to indicate that: 1) Individual delays can be identified analytically but not visually for short delay periods and large source to receiver distances, 2) Delay timing can be resolved to a few milliseconds, and 3) Results can be obtained from data collected at a minimal number of locations.

Jan 1, 1991

By Cathy McGinley, John Mullay, Clark Stancavage

The use of crater studies to evaluate explosive performance is a well-established practice in the Blasting Industry. Normally, this work utilizes larger charge sizes (>75mm) in order to minimize the influence of geological factors adjacent to the borehole. This can impose unwanted restrictions in the experimental factors accessible to investigation. Thus, for example, systematic studies of non-ideal performance in a somewhat practical setting is rendered quite difficult.

Jan 1, 1995

By Bradley C. Paul

Similar rock formations exhibit great variability in resistance to fragmentation during crater blasting. This observation was made during an attempt to calibrate the Kuz-Ram blast fragmentation model for crater blast geometries used in a modified in situ mining method for copper. The KuzRam equation is used to predict the fragment size distribution from blasting and includes a term called the "rock factor" to account for the fragmentation characteristics of the material. A data base of field scale crater shots in oil shale was available to supplement more limited data on copper ores. First, the blast geometry terms of the Kuz-Ram formula were modified to fit field data with various crater blast geometries. Rock factors were chosen to center the predicted curve on the curve representing observed fragmentation. Next, five possible sources of variability in rock factor were investigated: the grade of the oil shale, the aspect ratio of the charge, the type of explosive, the charge depth, and the rock itself.

Jan 1, 1989

By C. Partouche, T. Bernard

Blasting engineers are mainly concerned about fragmentation issues. Even further, this is the final goal of using explosives. A lot of models have been developed for controlling fragmentation distribution, but most of the time, they are based on physical phenomena using field data as input for rock characteristics. Fragmentation is a result of two phenomena: waves from the borehole, damaging and cracking the rock, and gas pressure, widening those cracks and spreading out rock fragments. This model simulates the P wave escaping from boreholes and the cracks created by these P waves. It takes into account rock characteristics, provided by digital imaging, and explosive characteristics coming from VOD measurements. What we need to focus on, is the interaction of P waves coming from each borehole related to different timing sequences. This paper presents several simulations that show the influence of the timing and the sequence accuracy on the fragmentation distribution.

Jan 1, 2002

By William C. Lane

The Pacific Northwest has an abundance of seamy, coarse granite and basalt rock. It is used primarily for road construction. Small quarries are opened nearest the road work to cut the cost of hauling. The crushers are portable. Small diameter holes 2 1/2" to 3 1/2" are placed close together to insure proper fragmentation. It is not unusual to load and shoot 100 to 700 holes 40' deep.

Jan 1, 1986

By Paul Muehl, Roger Lawrence

The massive sculpture taking place on Crazy Horse Mountain in the Black Hills of South Dakota, may Be the most unique application of precision blasting techniques in the world today, It is certainly the largest sculpture in history. And it is being carved not by the usual artist implements, but by engineering of explosives. This paper presents a review of the blastingasting techniques and challenges of blast earring the largest sculpture in the world,

Jan 1, 1991

By Mark S. Stagg, Rolfe E. Otterness, Stephen Rholl

The Bureau of Mines is engaged in research to develop and test high explosive fracturing and rubblization techniques that will enhance ore body permeability and thus increase recovery during in situ mining. The natural permeability of many ore bodies is too low to allow successful in-place leaching. These deposits could be profitably mined if flow rates of leach solutions could be increased. Blasting represents a potentially low-cost and effective permeability enhancement technique.

Jan 1, 1991

By Calvin J. Konya

When blasts are designed, we normally assume the best case situation. We assume that all burdens and spacings will be properly drilled, holes will be properly loaded, initiators will fire at the nominal time and the explosives will release their full energy. This type of precision can be obtained at a machine shop where precision equipment is available to do machining, however, in the field, no matter how well a blast is designed on paper, it most likely will not be done in the exact manner in the field.

Jan 1, 1990

By Trevor Garbutt, Peter Bellairs, Jason Sander, Glenn Shaw

The Yarrie Iron Ore mine is located in the Pilbara region of Western Australia some 200km eastsoutheast of Port Hedland, the closest large regional centre. The mine is owned by BHPIO who has contracted a large Australian mining contractor Roche Bros to be responsible for the total mining, crushing and trainloading functions. This paper describes a drill and blast optimisation program, resulting from the introduction of a new emulsion matrix called Titan@ Red used to manufacture both HANFO and pumped emulsion ANFO blends.

Jan 1, 1999

By Duane Skidmore, Calvin Konya

The supply crunch and cost rise for ammonium nitrate (AN) over the past year have been influenced by a number of factors. These include a general inflationary tendency, particularly great cost rises in fuel, and by a market condition in which demand for ammonium nitrate is great and supply is limited. Demand is largely confined to agricultural and explosives uses with explosives subdivided into mining, construction, and quarrying. The projections show that demand may be expected to increase markedly for the indefinite future in the agricultural and mining sectors of the ammonium nitrate market while fluctuating with indicators of economic activity for the construction and the quarrying sectors. Supply is projected to increase with plants being designed and built due to high need levels and commensurately high profit potential but not enough are planned to provide an equilibrium market. Constraints upon supply increases to match demand increases include shortages in the raw material, natural gas, high cost of investment capital, high equipment costs and long construction delays. The result should be, even under optimistic conditions, considerable shortage and resultant pressure for higher prices through 1979 for ammonium nitrate. The best hope for relief in the intervening years appears to be conservation. In blasting operations, the earliest and best proven route to conservation seems to be improved utilization available from application of highest available technology and most efficient current blasting practice.

Jan 1, 1975

By J R. "Dick" Daniel

One of the more common tasks in blast management is the adjustment of: shot geometry, explosive energy, and shot timing parameters to achieve changes in blast outcomes and costs. Many of these shot parameters, once a delayed blast is initiated, are modified by the development of new free faces which change the original or static input values to dynamic values. These newly generated dynamic values are easily calculated and find use in fine tuning shot adjustments and in rationalizing blast outcomes in a systematic manner.

Jan 1, 1996

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 Charles G. Wade

In the ensuing years nitroglycerin-based dynamites will continually be replaced by water-based explosives. Until recently, the choice of a high explosive water-based product was limited to some type of water gel. Now, there is another choice. New emulsions are available having several degrees of sensitivity over a wide range of diameters. This paper discusses the properties of these new emulsions, e.g., physical and thermochemical; the relationship between diameter and explosive properties; and the effects of aluminum on total energy. There is also discussion of some of the unique properties of emulsions, their advantages, and how they differ from water gels.

Jan 1, 1978

By Donald C. Clark

The Blasting Contractor as an Insurance Risk involves a discussion of changing times in the insurance market and changing methods of operation in the construction industry. Since the advent of Internal Revenue Service~1 and Occupational Safety and Health Act~2 regulations by the Federal Government in the early 1970's, operations have changed. Many small users of explosives have discontinued any use in favor of subcontracting the drilling and blasting to specialists. This change in operations along with the change in the insurance market has created coverage problems which is the subject of discussion of this paper. Although no definite conclusions are reached, it is an attempt to promote understanding and further the efforts toward equitable solutions.

Jan 1, 1977

By J R. "Dick" Daniel

One of the more common tasks in blast management is the adjustment of: shot geometry, explosive energy, and shot timing parameters to achieve changes in blast outcomes and costs. Many of these shot parameters, once a delayed blast is initiated, are modified by the development of new free faces which change the original or static input values to dynamic values. These newly generated dynamic values are easily calculated and find use in fine tuning shot adjustments and in rationalizing blast outcomes in a systematic manner.

Jan 1, 1996

This paper presents a brief discussion of three case histories to illustrate several aspects of the question of blasting in or immediately adjacent to concrete. The results demonstrate a need to make dramatic upward revisions in previous criteria, whether it be the standard particle velocity criteria or damage response spectra bounds, - especially those which include conservative upper limits of constant acceleration for the high-frequency portion of the spectrum. It is demonstrated, also, that conventional off-the-shelf blast-monitoring instruments are not capable of monitoring small blasts at close range. Both the frequencies and the levels of effect are beyond the range of such instruments. These case histories suggest further that there is a need to review the applicability of certain wellknown equations of elasticity.

Jan 1, 1980

By C De La Cruz

The use of a thin-film piezoelectric stress gauge to determine the pressure profile in a detonating explosive has been demonstrated. These PVDF gauges have measured, in the borehole, the Chapman-Jouget pressure and the release adiabat of the detonation products for several explosives including ANFO and ANFO/emulsion mixtures. The technique can provide: (1) a direct measure of the blasting stimulus, (2) a sensitive QA tool for the blaster, and (3) a means to examine the magnitude and effects of preshock from adjacent bore holes. The PVDF pressure gauge is self powered, can measure pressure from a few bars to 400 kbars, has high time resolution (0.05 µsec), and is easy and economical to use.

Jan 1, 1997