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By Harnish Miller, Scott G. Giltner

One of the concerns with locating radioactive waste storage sites in salt deposits is how to permanently seal the underground storage areas once they have reached their storage capacity. The compaction of salt using explosives has been identified as a potential method of producing permanent seals in both entryways and shafts to storage areas. This paper describes the test procedure and results of a preliminary investigation to determine the feasibility of utilizing explosives in the compaction of salt. Three simple tests were carried out to measure the degree to which loose salt could be compacted.

Jan 1, 1996

By Edward J. Walter

Vibration control is affected by many factors which are difficult to isolate and evaluate. Occasionally a circumstance occurs in which one factor appears to predominate and its effects can be evaluated. Changing rock characteristic or lithologic variation is one of these factors or parameters. In a recent seismic monitoring project, lithologic variation in the form of hard lenses occurring suddenly and randomly in the rock to be excavated caused sudden and large increases in vibration level. Data are presented to illustrate these effects, and procedures used to control these effects are described.

Jan 1, 1981

By Minoru Kawamura, Yukio Kato, Yoshikazu Hirosaki, Satoru Suzuki

A wireless blasting system for tunnel construction which consists of a loop antenna, oscillator and blaster, has been developed. The basic technology of this method had been studied in the 1970s to develop a wireless initiation system for undersea blasting and has been successfully used as a Remote Controlled (RCB) system in the Honshu/ Shikoku Bridge construction project in Japan.

Jan 1, 1998

By Geraldine Rosenthal, Gadi Yohan, Roman Benram

Description of Project: Tamar Group’s civil division was awarded a contract to implode the Sun Hotel, an abandoned 14-story building located along Bat Yam’s coastline, roughly two kilometers south of Tel Aviv, Israel. On Nov. 6, 2012, Tamar Group’s experts positioned explosives in strategic locations of the building, targeting its central pillars, which then caused the building to collapse within seconds. Tamar Group used a relatively small amount of explosives in order to generate a well-controlled blast. This is the largest scale demolition carried out in Israel to date.

Jan 1, 2014

By J R. Hearst, T R. Butkovich

Explosive-induced fracturing and permeability enhancement far from a free face were studied. A one-dimensional computer program, SOC, was used to predict the total failure-associated distortional strain, ef. Laboratory and field experiments associated the calculated ef with the observed fracture and permeability enhancement. An ef value of 0.015 corresponded to the observed radius of effect, which was about seven times the cavity radius and was consistent with predictions from SOC and from the literature.

Jan 1, 1976

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 Todd B. Harrington, Dennis M. Lydon, Walter B. Sudweeks

Heavy ANFO products made by mixing ANFO (or AN prills) with a relatively small amount of emulsion (typically 15-30 percent) have become very popular in recent years. They are less expensive than straight, sensitized emulsion and maintain the good shooting characteristics of ANFO but have higher bulk strengths. Their use, however, is generally limited to larger diameter, dry boreholes. Smaller diameter, wet-hole quarries have not been able to widely utilize this low cost bulk product.

Jan 1, 1989

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 James G. Stuart

For precise control and timing of a blast, people use electric detonators. Most of these contain a fine metal “bridgewire,” that heats to the required burning temperature when electric current passes through it. Users should be careful. Stray voltage can fire these detonators. Some designs are particularly susceptible to electrostatic-discharge (ESD). We will discuss some of the accidents we have encountered in our forensic work. We will recommend specific safe procedures for handling and firing these devices.

Jan 1, 2005

By Duane A. Houkom

Explosive demolition of concrete has been accepted as a safe and economical means of concrete removal for many years. I imagine that the early concrete blasters were experienced rock blasters who applied their knowledge to just another formation. Since a concrete foundation is generally located in a congested area, the owner is willing to accept the higher costs of mechanical removal,rather than promote "a new idea" to his management. This attitude is rapidly changing,making it possible to use the advantages of explosives in more congested locations.

Jan 1, 1982

By R Holmberg, C Sjoberg, B Larsson

This paper describes the excavation of an underground naphta storage facility at Stenungsund in Sweden. The main purpose with this paper is to give an overall view of how the excavation was carried out and in what type of bedrock the storage was built. Emphasis has been done to highlight the importance of using cautious blasting to avoid blast damage in the remaining rock. Attempts has also been done in order to evaluate what the degree of Swedish cautious blasting has meant for the rock support costs during the construction period.

Jan 1, 1984

By Daodu Opeyemi

This paper describes several damages of blasting operations on some case studies, analyzes causative factors, and emphasizes preventive measures. Due to several complaints from some host mining communities as a result of blasting operations; two quarries from Nigeria suburbs were visited for study. The blasting design parameters in the mining companies were examined. Also, the history and existing conclusion of the neighboring buildings were studied using structured questionnaire, personal contact and visual examination. From the study carried out, it was discovered that varying negative environmental and socio economic problems resulted from the effects of vibration and flyrock on the nearby agro mining communities. The consequences are not limited to distortion of landscape but also include extinction of some animals, poor agricultural productivity; such as damages to economic trees and reduction in the yield of crops, health problems as a result of shock resulting to psychological disturbances, communal conflicts, blast induced cracks of structures and sometimes total collapse of host agro mining buildings, thus indicating that most mines did not comply with the safety concept of the existing environmental laws and regulations. Based on the results of the study it was recommended that proper blast design of quarries/mines should be conducted and the compulsory use of seismograph will be crucial in developing predictions. Environmental impact assessment should always be conducted before, during and after each blasting operation. Other possible control of vibration, flyrock and airblast, are also discussed in the paper

Jan 1, 2009

By D. Bartley, R. McClure, W. Reisz

Ever since the 8ms criterion was developed in the early 60’s there has been an ongoing debate among many blasters as to its actual value in controlling ground vibration. The perpetuation of the myth surrounding the 8ms window can be partly attributed to its simplicity and convenience as a means for regulatory compliance. Unfortunately, the mindset that many blasters have adopted has hindered the development and use of more effective techniques and in many cases can actually be counter productive to vibration control.

Jan 1, 2006

By Paul V. Sterk, James Wieser

Mining in underground situations requires constant change due to changing ore bodies and economics. The Homestake Mine in its 122 years of existence has gone through numerous changes due to these factors. Recent sustained low prices in gold and ore bodies that are smaller or within mined out areas have forced the mine to reevaluate how these ore blocks will be mined. This paper will describe the design, drilling, and blasting of a complex ore block using the blind raise uphole bulk mining method.

Jan 1, 1999

By Henry P. Van Ormer

This paper discusses some basic fundamentals in compressed air system design and layouts that should always be considered in planning or evaluating a compressed air distribution system in Construction and Mining. Often times, mining operations use central air or "power house" type systems that more closely resemble a typical industrial or plant compressed air distribution system. This paper does not attempt to cover this type of system.

Jan 1, 1975

By D Wilson, R R. Vandebeek, R A. Bowes

"As business opportunities are sought around the world, the explosives industry must oftengrapple with the United Nations Transport of Dangerous Goods Recommendations.Canadians have problems in this area that are similar to those of other countries. Thispresentation outlines, through a case study, how a container for shipping ""explosives"" wasdesigned, tested and approved for use by the Chief Inspector of Explosives, the""Competent Authority"" for Canada."

Jan 1, 1993

By F M. Dantini, P Berry

An experimental investigation on the trend of cratering induced by explosives placed on rock masses was carried out. By using various types of explosives and rocks having different geomechanical parameters, it was possible to evaluate the influence of the explosive-rock coupling. Furthermore, the importance of the parameters defining the rock and the explosive for the absorption of energy induced in the rock mass, is pointed out.

Jan 1, 1981

Blasting in a development heading or breasting operations starts from a cut. The void created by the cut provides a free face for the remainder of the round. It is the most critical part of the round because the later firing charges cannot pull to the desired depth unless the cut comes out as planned. The Burn cut is most commonly used in Canadian mines.

Jan 1, 1995

By Lawrence C. Schneider

In the past decade regulations governing the manufacture, distribution, storage, and use of explosives have proliferated. These laws have been developed by a host of federal agencies with no coordination. The result has been contradictory and impractical standards, which once adopted, are resistant to change or repeal. The current OSHA standards are one example which is examined in detail. The Commonwealth of Kentucky has made progress in modifying these standards, and still providing protection to the blaster and the public.

Jan 1, 1981

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