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By James D. Cook, Dan McCutchen

Effective overburden casting requires the efficient use of todays explosives and initiations systems if a mine is to survive. This paper uses a major coal stripping operation as an example of the proper application of explosives and initiation system to their conditions.

Jan 1, 1994

By C M. Deosthale, V N. Pangal, M N. Rao

New Mangalore Port is the most important port in Karnataka State, on the west coast of India on Arabian Sea. It handles export of iron ore, granite, coffee, spices etc and imports of crude oil, fertilizers etc. Since 1991, after economic liberalisation by the Government of India, the exports and imports at this port got a boost. Hence the Port Trust felt the need to increase the draught by about 3 to 5 meters for access to bigger ships. In response to a global tender in 1995, the Dutch Dredging Company got the contract to remove 30,000 cu.m of hard granite bed rock, covering 28,000 sq.mtr. area for the Turning Circle and oil Jetty. The operations of drilling, blasting and dredging were to be carried out to deepen the area to about 15 m draught without affecting the normal trade at the Port. This was a time bound contract to avoid interruption by severe Monsoon rains.

Jan 1, 1999

By Anderson Meireles, Vladimir Carrasco, Carlos Feliciano

Adopting new technology in drill and blast requires a structured implementation process, as it represents a significant change in a traditionally conservative industry. It involves addressing initially unknown implications. As the problem is not yet acutely felt, developing a market strategy must be approached from the customer’s perspective, considering how the product can optimize their activities or enhance flexibility. To achieve this, it is essential to have a comprehensive understanding of the context of the customers identified in the deployment process pipeline. This paper discusses aspects of introducing wireless initiation technology - the initiation of primers through a magnetic field without physical connections - in Brazil. Additionally, it presents a case study of the application of a structured process of sales with purpose in an underground mine. By identifying key opportunities that were highly profitable for the client, the necessary awareness was created, leading them to recognize the technology as an enabler for exploring their mineral deposits in a new way which allowed a successful change management process. Based on the applicable technique, a preloading project was developed to maintain inaccessible areas with high-grade precharged with the area loaded with wireless primers acting as a temporary pillar and controlling dilution throughout the orebody. Once the excavation of the stope was completed, the pillar was successfully blasted and the material - once considered lost in the original plan as a rib pillar - was recovered after serving its structural function. Through this method, the metallic recovery of the stope increased without dilution losses. Demonstrating economic viability and stablishing the previously unknown technology as a strategic tool for optimizing stope recovery.

Jan 21, 2025

By Cathy Aimone-Martin, Frank Achuff

The New Mexico Department of Transportation (NMDOT) and the Federal Highway Administration (FHWA) have let a contract to Sierra Blanca Constructors for a design / build contract along 38 miles US 70 in Lincoln County, New Mexico. The project will improve safety of travel along the corridor and facilitate the adopted economic development goals of the state. Proposed improvements include widening the existing highway from two lanes to four lanes, providing left turn lane options at selected locations, improving access for businesses and residences, aesthetically enhancing retaining walls, improving storm drainage and replacing the existing pavement with a 30 year mechanistic imperialistic perpetual pavement design. The US 70 Hondo Valley highway project is situated in a narrow valley with steep limestone walls, passes along a Scenic Byway and numerous historic ranching communities with structures that date back three centuries. The scope of work included requirements to monitor and mitigate blasting, noise, and vibrations. The contract was very presumptive with regard to blasting design and procedures. These included visual impact mitigation to treat and stabilize slope cuts, the Migratory Bird Treaty Act protecting roosting and nesting birds from airblast, and the protection of historic and cultural features such as acequias, wells, and structures. Public involvement affecting the rock blasting design has come from citizen task forces and committees concerned with highwall aesthetics and preserving the scenic byway and cultural resources. Constraints placed on the blasting program from agencies and the communities are often at odds. For instance, blasting must produce stable yet natural-looking walls to preserve aesthetics. Restrictions have been placed on pre-splitting and smooth-wall blasting yet safe slope are of the highest priority. This paper presents details of the design/build process undertaken by the contractors to conduct blast rock in an environmentally sensitive region. Blast designs consistent with good construction practices and used to comply with the many federal and state highway stipulations are described.

Jan 1, 2004

By Robert Hopler

In part four, the instrumentation used to detect the vibrations from the 1876 Hell Gate (East River, New York) reef-clearing blast was discussed. The apparatus consisted of cups of mercury and microscopes or other magnifying instruments to detect ripples or waves on the surface of the liquid metal.

Jan 1, 2007

By Thierry Bernard

New technology to automatically design a blast based on autonomous drone. The process of flying a drone, calculating the 3D cloud of points, generating the critical face profiles and placing holes automatically according to burden specification becomes fully automatic. A nice time saving with more efficiency

Feb 1, 2020

By Harry L. Siebert, Thomas Gelormino

Rock excavation in urban areas occurs with maximum public exposure and, with the aid of explosives, is one of the challenges facing this industry today. Such excavation is also a hidden factor in areas of new growth, revitalization or upgrading existing facilities in or near urban areas.

Jan 1, 1985

By D T. Froedge

A new system for acquiring blast vibration data and a method for presenting that data in such a way that there can be an extraordinarily enhanced insight into the understanding of vibrations produced by blasting is described in this paper.

Jan 1, 1989

By G. F. Revey

When rock blasting occurs near new concrete of varying age, engineers representing project owners often express concern that vibration from the blasting will crack nearby concrete. Regulations and/or specifications for civil construction projects usually include particle velocity vibration limits intended to protect concrete. In some cases specified limits are unreasonably low and needlessly restrict and increase the cost of excavation work. This paper discusses how methods of predicting resulting flexural strains caused by blast-motion can be used to develop safe and reasonable PPV limits to protect new concrete. Three case histories demonstrating how these evaluation techniques were used to establish higher PPV limits designed to protect concrete of various structural condition are also presented.

Jan 1, 2006

By Karl Ingmarsson

A model for drilling productivity and total drilling cost is presented. It specifically addresses down-thehole drilling, but also covers other drilling methods. The important factors are: 1, productivity in tons drilled; and 2, total cost per drill ton. For non-blasthole applications these factors are measured in drill feet and cost per foot. The model focuses on the entire system and allows the operator to optimize the system based on individual drilling conditions.

Jan 1, 1998

By Zahra Hosseini, S. Hassan Khoshroo, Mohsen Amirrahmat

The Sarcheshmeh Copper mine will be developing its open-pit in order to reach to the remaining ore in the deposit. One of the problems regarding the development plan is the ore handling system from the pit. After its development, the pit depth and its daily production will be increased. Therefore, the present transportation system (shovel and trucks) can no longer be used efficiently. It is necessary to use a new system that can reduce transportation costs and handle the new amount of blasted material at the same time. Studies show that an in-pit crusher and conveyor belt is the most suitable system that could be used in this situation. One of disadvantages of the conveyor belt, however, is its limitation in the particle sizes that it could carry. Consequently, size distribution resulting from the fragmentation process is an important parameter in choosing an efficient conveyor belt system. The size distribution of the fragmentation process also affects the operations following blasting. The determination of this parameter allows the optimization of blast design and explosives. Hence, during this project, the size distribution of blast fragmentation in the different types of ore at the Sarcheshmeh mine was determined by the image analysis technique. Numerous digital pictures were captured of the different blasted faces to prepare a representative sample of each kind of rock. They were then analyzed using the GoldSize image analysis software. Results show that fragmentation in the blasted rock is relatively high. It is therefore expected that an appropriate conveyor belt could be selected for further developing the open-pit mine at Sarcheshmeh.

Jan 1, 2004

By R Fox, R Watt

On behalf of ICI's group of explosives companies around the world, a research programme is being undertaken to develop a new electrical shotfiring system which will have markedly improved safety features and operational advantages over existing initiating systems. The paper describes the development of the 'Magnadet' Electric Detonator and 'Magna' Primer and the field experience to date. It also indicates those areas where further work is being carried out on modification of the basic designs to meet specific application requirements.

Jan 1, 1981

By Harley Cheema, Brandon Fryman, John Tatom

A new magazine propagation model has been proposed by the IMESAFR Science Panel for eventual implementation into the IMESAFR QRA program. Initial results from this QRA propagation model are now available.

Feb 1, 2020

By Thomas M. Keevin, Gregory L. Hempen

A study was conducted to measure underwater pressures associated with confined borehole shooting used to remove rock for The Kill Van Kull Deepening Project, U.S. Army Corps of Engineers, New York District. A major natural-resource-agency concern was the potential for fish mortality during explosive rock removal. Currently, fish mortality models are based on testing programs that exposed captured organisms to open-water blasts. Natural resource agencies, without in-house explosive engineering expertise, generally are not familiar with the physical properties of blasting underwater. Confined shots are most often used for demolition and rock removal underwater. Pressure amplitudes from confined blasts are significantly reduced as compared to open-water blasts that, are commonly used for fish testing The duties of natural resource agencies are made even more difficult by the lack of published data on pressures associated with confined blasting. As a result, explosive weights for confined shots mistakenly have been used to run mortality models that were developed using open-water blast pressure data. This study was conducted to collect pressure measurements during rock removal for the KVK deepening project and compare those data with computed peak pressures for open-water explosions.

Jan 1, 2005

By J R. Brinkmann, S G. Giltner

Nearly all of the South African gold mining industry still uses fuse and igniter-cord initiation systems. Over the past 30 years numerous attempts at developing new initiation systems have not yielded a viable alternative. New initiation systems for narrow stopes are currently being developed by various concerns and the likelihood of these efforts producing feasible alternatives is greatly improved due to the recent advances in electronics technology. The greatest potential benefit of alternative initiation systems is increased production rates through improvements in accuracy and reliability of firing over that of fuse/igniter-cord. Another important feature is the capability of millisecond delay firing as this can lead to reduced stope cleaning times by way of enhanced rock throw and improved fragmentation characteristics.

Jan 1, 1989

By P. Katsabanis

Researchers in the field of blasting have been trying to develop ways of predicting fragmentation in the last few decades. The Kuznetsov equation estimates the average fragment size, XJ~, based on explosive energy and powder factors. Cunningham calculates the uniformity of a fragment size distribution using drilling accuracy, blast geometry and a rock factor A associated with a “blastability index”, which can be estimated from the jointing, density and hardness of the blasted rock mass. Knowing the mean size and the uniformity index, a Rosin-Rammler distribution equation can then be derived for calculating the fragment size distribution in a blasted muckpile. Analysis of existing data has revealed serious discrepancies between actual and calculated uniformity indices. The current integrated approach combines the Kuznetsov or similar equation and a comminution concept like the Bond Index equation to enable the estimation of both the 50% and SOoh passing sizes (X& and X& ). By substituting these two passing sizes into the Rosin-Rammler equation, the characteristic size (Xc ) and the uniformity index (n) can be obtained to allow the calculation of various fragment sizes in a given blast. The effectiveness of this new fragmentation prediction approach has been tested using sieved data from small-scale bench blasts, available in the literature. This paper will cover all tested results and a discussion on the discrepancy between measurement and prediction due to possible energy loss during blasting.

Jan 1, 2001

By Bill Bauet, John Anderson

There are always security concerns when explosives are transported and stored, and these concerns are intensified in peacekeeping operations where explosives could fall into the wrong hands. MREL Specialty Explosive Products Limited has developed FIXORTM, a new approach to neutralizing landmines and unexploded ordnance (UXO). The product consists of two precursors: a flammable liquid in one plastic container and a totally inert powder in another; neither of these precursors is classified as explosives. Both precursors are approved for transport by land, sea and commercial passenger airfreight. The precursors are mixed to form an explosive immediately prior to placement next to the UXO or landmine. Initiation is by blasting cap or detonating cord.

Jan 1, 2001

By John A. Franklin, Norbert B. Maerz, D Linn Coursen

Accurate measurement of blast fragmentation is important in mining and quarrying operations, to monitor blasting and optimize blast design. A new digital photoanalytical method to measure the block size is presented here. Photographs of the broken rock are digitized, apparent size distributions measured, and corrections made for overlapping blocks, by means of an empirically derived correction function. The method was tested during recent full-scale blasting tests in Virginia, USA. It shows great potential as a practical aid to predicting, monitoring, and controlling the quality of the fragmented rock.

Jan 1, 1987

By Thierry Bernard

To be able to precisely predict the result of a mine blast before pressing the button is a goal for many blasters due to the environmental and economic constraints of our century. Based on the fundamental fracturing of the mechanism of rocks by explosives, the most recent research in digital modeling, the power of present computers, and the possibilities offered by drones, we have designed a realistic digital 3D simulation model for mine blasts

Feb 1, 2020

By Jorge Alvarez

In a large-scale open-pit mining operation, continuous efforts are made to control damage to the slope walls. An essential tool in this effort is determining the PPVc (critical peak particle velocity) in areas of interest. By knowing this value and generating criteria, drilling and blasting designs can be established to reduce vibrations that affect wall construction. It is crucial to understand that the PPVc changes as different mining phases develop, especially due to exploitation on the benches, which leads to vertical inherited damage. Therefore, it is imperative to regularly update the PPVc based on field tests that provide accurate data. With this information, vibration damage criteria can be established, and drilling and blasting techniques can be designed to minimize the impact on the remaining rock mass. This document presents a methodology for generating scaled criteria that best represent the reality of the rock mass.

Jan 21, 2025