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By Zhang Zhenyu, Wu Xinxia

The blasting quarrying technology of rock material of rock-fill dam is one of the more complex problems in the field of engineering blasting at present. The Kuz-Ram model is not suited to predict fragmentation distribution under the geology condition of Tianshengqiao(TSQ) fist-step power station. The modification of kuz-Ram model is discussed. With reference to the idea of model establishment of Kuz-Ram model and according to the results of experimental blasting in-situ, two fragmentation prediction models-TSQ-1 and TSQ-2 model are presented which are adapted to the particular condition of rock material querying blasting of rock-fill dam with concrete facing of TSQ first-step power station. The rapid judgment method of qualified grade material and the method of optimizing blasting parameters are also presented in this paper.

Jan 1, 1998

By George E. Jackson

ANFO, as a blasting agent, is used in large quantities in coal surface mines. It can be purchased on the open market or through reliable suppliers. The blaster in the field must assume that his ANFO is homogeneous, consistent, and nearly identical on a daily basis. A quality control program will enable him to be assured of the correct product. Therefore, the material cost and operational efficiency can be better controlled.

Jan 1, 1978

By Michael S. Wieland

Delay detonators that are damaged by cross-hole wave interactions degrade blasting work and raise the risk of incidents. Damaged detonators impose risk, because they can retain sensitive explosives that respond to stray energy during recovery, inspection or disposal. Laboratory techniques were developed to rank the ruggedness of delay detonators under replicated field-shooting conditions. The hazards are tremendously magnified if trial detonators are installed directly in secondary explosives to rank initiation strength. Therefore indirect ranking techniques were sought that mitigate the risks without compromising the worthiness of the method. Four types of hardware fixtures, referred to as simulators, were developed to yield distinct forms of transient compression. The shock and rift versions generate compression pulses representative of in situ waveform components. The waiting time, until the trial detonator functions, duplicates typical delay periods. The trial detonator is mounted within water, which has a density and inertial resistance comparable to most blasting explosives. The work output from the trial detonator explosion is registered as fixture wall-expansion. This work output determines malfunction results, regardless of which type of simulator is used.

Jan 1, 1997

By John C. Didlinger, John L. Didlinger

As we begin the pre-blast survey we need to decide on the number of holes needed for production and a detailed highwall inspection. The survey consists of checking the highwall and placement of barrier cones. At the Elmhurst Chicago Stone Company, Barbers Corner Plant, we use 18-24" orange highway type safety cones. These cones are easily noticed because of their high visibility color in all weather conditions and are placed approximately 20-25 feet from the face and approximately 50 feet apart along the highwall, then the area is checked for back break, under cut, over hang, surface filled area and clay area. This deposit is unique because of the number of clay filled areas and slip seams that meanders through the deposit plus a fault that runs North-Northwest and South-Southeast. This particular limestone deposit is overlaid with glacial sand and gravel and the top weathered stone wanders plus or minus 10 feet in 1400 feet.

Jan 1, 1996

By Gordon M. Matheson, David K. Miller

Sinkhole development in karst terrains is a serious problem and risk to facilities built in these areas. The potential for sinkholes are a function of many things including the chemistry of the underlying rock, the location of water conductive fractures and fissures in the rock, the natural fluctuation of the ground water table, vibrations from various sources and surface regrading activities. When sinkhole open near quarry operations the occurrence of these features is occasionally attributed to vibrations from quarry blasting. The purpose of this paper is to review the evidence regarding the development of sinkholes as a result of quarry blasting. In general, it has been found that sinkholes result from collapse or piping of overburden soils into cavities or caverns developed within underlying carbonate rocks that have been in existence for many thousands of years. The overburden soils in karst areas are typically clayey and as a result are not subject to densification or liquefaction as a result of vibrations. The primary cause of an increased rate of sinkhole development can be attributed to changes in the ground water table or local surface water drainage. These changes may be caused by seasonal fluctuations, ground water level lowering in drought periods, dewatering of excavations or quarries, or local changes in surface drainage resulting from grading activities.

Jan 1, 1998

By Heins Walter Wild

Detailed investigations on various configuration kinds of cut with respect to drilling-technological and blasting-technological properties as well as with respect to cost effectiveness have been carried out in Germany.

Jan 1, 1995

By Michael David Wilkins, Paul N. Worsey

Little research has been published on stemming blast holes, particularly what happens during the process. Previous work has concentrated on the performance of the inert material to find the best way to seal the hole and retain the explosive energy, at the exclusion of determining what happens during the loading and stemming process.

Jan 1, 1998

By C H. Dowding, P W. Linehan

Many of the technical and non-technical or human problems associated with blasting can be minimized through a proper preconstruction test-blast program.

Jan 1, 1986

By Donald F. Rapp

Improvements in non-electric initiation systems have given the blasting industry more choices than ever in controlling blast results. By incorporating blasting requirements and system attributes, timing patterns are only limited by the creativity of the shot designer. This paper will discuss the basic groups of non-electric initiation systems, their attributes, and how to select the optimum system for the job.

Jan 1, 1991

By J MacPhail, H Gardner

This paper discusses reasons why users of rotary air blast hole bits encounter premature bit failure due to bearing failure. It also discusses a lubrication system designed for rotary rock bits to combat bearing failure.

Jan 1, 1996

By Jin Jingzhi, Wang Xuguang, Guan Li, Li Jianjin

Emulsion explosives are gaining a wider and wider commercial market and are displacing other composite slurry technologies. However, the grease-like state and essential thermodynamic instability of emulsion explosives cause inconvenience in production, transportation, storage and use and lead to gradual changes in performance. Emulsion powder explosives are designed to avoid these disadvantages. The formulation, process and properties of emulsion powder explosives made through a spin flash technology are described in this paper.

Jan 1, 1997

By William E. Hill

The blasting program at the Valdez Creek Placer Mine must deal with challenging situations throughout the year. During the short summer, extreme water conditions must be confronted, while the winter months present problems of a different nature, where the overburden freezes to a depth of up to 18 feet. These obstacles require techniques borrowed from hardrock blasting combined with creative experimentation to overcome.

Jan 1, 1994

By Zhang Shixun, Wang Xuguang, Zhong Yinting

The Mongol-Russian Joint Mining and Processing Cu-Mo Corporation Erdenet signed a contract with BGRIMM for building a plant to produce 10,000 t/y multitype emulsion explosives by using BGRIMM emulsion explosives manufacturing technology. In order to ensure the realization this contract, we have done a series of studies on the design of technological process and the selection, layout of the production equipment, and made a success.

Jan 1, 1997

By He Guangyi, Han Zhilong

This paper introduces the new technology of deep-hole blasting with water-soil mixed stemming to exposed stonework. Nine aspects of advantages are drawn in the paper based on tests of different types of charge and stemming under the conditions of different geology, height of bench and diameter of drill.

Jan 1, 1998

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 Mario Coderre, Andre Pinsonnault, Francois Lefebvre, Pierre Groleau, Yves Newman, Christian Pouliot

"This paper describes the blasting methods used to excavate the tailrace channel at theLaforge hydroelectric plant. It also shows the importance and versatility of the dopedemulsion explosives used in this project."

Jan 1, 1993

By Pierre-Louis Migairou

After a period of development and experimentation ranging over 20 years, electronic detonators have now come to maturity and are becoming the first choice in many diverse applications like tunnelling, civil works, demolition works, quarrying, large scale open pit mining and underground mining. This paper demonstrates the versatility of electronic initiation systems by detailing a number of case studies in several applications as different as their geographical locations, and gives specific reasons explaining the popularity of electronics in each case.

Jan 1, 2009

This paper discusses development, test data, field trials, performance, application and possible economics of high-energy blasting agents fueled with Nitropropane that can be bulk loaded into downholes or packed into waterproof packages at densities between 1.10 and 1.25 gm/cc and that yield calculated detonation pressures of 50 kilobars in small diameters to 100 kilobars in diameters over six inches. Using high-density nitrate, downhole densities of over 1.4 have been attained in field trials with correspondingly high calculated detonation pressures.

Jan 1, 1977

By J T. Keim

Members and guests of the Society of Explosive Engineers, it's indeed a pleasure for a longtime practical user such as myself to have the ears of so many explosive experts for a few minutes just to express my feelings and concerns on blasting as well as the feelings and concerns of many other users and operators.

Jan 1, 1978

By I. Petropouleas, J. Croll, R. Bassett

A programme of tests on controlled internal explosions to a class of circular reinforced concrete columns, has allowed the relationships between the blast energy and the extent of local damage to be understood. These tests have also demonstrated the important additional effects on the damage levels of preexisting axial loads.

Jan 1, 2006