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By Zhou Jiahan Wang Feng

This paper introduces the mechanism and the operating process of dike building by silt squeezing blasting. DBSSB (dike building by silt squeezing blasting) has the following advantages: shorter construction period (the construction period is decided only by the speed of rock materials filling)greater consolidation of the body of the dike, more structural stability, smaller settlement. Therefore by conventional standards the same dike can be designed with a smaller cross section than other construction methods, and at a reduced cost when enough rock materials can be provided in site.

Jan 1, 2006

By Gordon F. Revey

Hanging Lake Joint Venture recently excavated two conventional 42 foot diameter highway tunnels in the difficult ground conditions of Glenwood Canyon, Colorado. This paper outlines the type and success of the various Controlled Blasting Techniques that were used to minimize overbreak in the portal and tunnel excavations. The different Smoothwall and Cushion Charge loads used in the different ground types are described in detail. Delay Timing and Drilling Pattern variations are also discussed.

Jan 1, 1991

By J R. "Dick" Daniel

In the fall of 1988, The Cannon mine decided to investigate a central blasting system based on conventional electric blasting detonators being used to initiate rounds primed with Nonel detonators. The advantages of this hybrid detonator system were viewed as being safety and cost effectiveness. A study was done reviewing the safety aspects of utilizing a permanent blasting line installed throughout the main haulage drifts to a central blasting station located at the mine portal. The study addressed the following potential safety hazards: radio frequency induced current, stray current from both electrical utilities and transmission lines, galvanic and electrostatic sources of extraneous current.

Jan 1, 1989

By J Edmund Hay, T S. Bajpayee

The Bureau of Mines is developing a test to determine the initiating strength of commercial detonators. Various tests of "detonator strength" are in use, but many of them do not correlate well with each other, and so far, there is little evidence that any of them correlates well with the ability of detonators to initiate detonation in an explosive. Therefore, the Bureau decided to attempt a measurement of the ability of detonators to initiate detonation. To this end, an explosive mixture of adjustable sensitivity was developed. This mixture was nitromethane sensitized with ethylene diamine, the sensitivity being "fine-tuned" by the addition of nitropropane.

Jan 1, 1992

By William R. Adamson, Carlos R. Scherpenisse

The successful development of surface mining operations depends, amongst other factors, on the successful creation of final pit walls which offer long term structural stability. The achievement of such walls will be much more feasible if the mechanisms of rock mass deterioration in the mine are well understood, permitting the control and reduction of this deterioration (or damage). The role of drilling and blasting in causing damage is widely accepted but rarely fully quantified. It is also true that the dependence of rock mass damage on vibration levels is only incompletely understood and little accurate field measurement is routinely conducted in the mining industry.

Jan 1, 1998

By John M. Bolger, Keith E. McMaster

Excessive salt fines are undesirable in underground salt mining as they are considered a costly waste by-product. This paper describes an extensive explosive application program conducted at The Canadian Salt Company Ltd, located in Pugwash, Nova Scotia, Canada. The prime objective of the program was to reduce the quantity of fines generated from this company's underground production blasts. The program was known as the "The Fines Reduction Program".

Jan 1, 1996

"Recently, an effort was made to calibrate the Riedel-Hiermaier-Thoma (RHT) material model to reproducethe behavior of granite under impact and explosive loading conditions. The study concluded that the materialmodel captured the phenomenon of compressional damage in granite due to such loading conditionsfairly well. The present work uses hydrodynamic modeling with the calibrated RHT model to estimate thefines generated around a blasthole. This can improve the calibration of different size-distribution empiricalmodels and enhance the prediction of fines."

Jan 1, 2012

By Michael M. Jackson

"The mining industry has for some time compared explosive energy requirements to theresults obtained using ANFO. Drill patterns, powder factors, and explosive bulk strengthshave all been developed based on the detonation characteristics and blasting resultsexhibited by ANFO. However, there are some mining applications where the use of ANFOcan cause over_blasting if loaded to acceptable collar heights or surface breakage problemsif collar heights are reduced. A specialized, low strength, low density water gel explosivehas been developed that has loading densities in the range of 0.4 to 0.7 g/cc. The uniquecharacteristics of the low density water gel explosive is that the explosive can beformulated with a range of available bulk strengths while maintaining excellent detonationsensitivity for use in applications involving ore/waste control, restricted blast patterns,small bench heights, etc. The"

Jan 1, 1993

By Erik Nygaard, Klaus Voges

ANFO is the most used industrial blasting agent in the world, and is often used as a reference for comparison of other explosives. It is known to work very well under dry conditions in large borehole diameters, whilst in small borehole diameters increasing amounts of toxic fumes (CO, NO and NOz) can be formed. In underground blasting, problems can also occur with reduced visibility caused by unreacted ammonium nitrate and overall composition of the detonation fumes. ANFO is made by mixing Ammonium Nitrate Porous Prills (AN-PP) and fuel oil. We have measured velocity of detonation (VOD), toxic fumes and visibility after blasting of ANFO in 54x2 mm steel tubes, and the differences are remarkable: By using an AN-PP grade developed for underground blasting and small diameters, the following can be obtained:

Jan 1, 2001

By Paul Worsey, Gillian Worsey

The basic blasting class at Missouri S&T blast in the quarry at the experimental mine in preparation for the International Intercollegiate Mining (Mucking) Competition in April 2014.

Jan 1, 2015

By Tom Burleson

High-speed photography has proven to be an extremely valuable tool for the evaluation of blasting practices in the Warrior Coal Basin. A research project, coordinated by Nelson Brothers Inc. and The University of Alabama's Mineral Engineering Department, has centered on the use of high-speed photography to study and analyze blast performance. A large number of production shots in this region has been filmed and studied. The data obtained from the films have been used to establish graphical relationships between certain blast parameters and overall shot performance. These relationships will be used to develop a computer model that will estimate cast results from a given burden explosive energy combination. This paper describes the methods and procedures used to develop these relationships. The results of the research are discussed along with plans for continuing the research project.

Jan 1, 1988

By Jiang Han, J. F. Shao

Based on the rock blasting engineering, The Self-Organizing Map (SOM) network has been implemented for the concept and method of rock blastability classification. The Self-Organizing Map (SOM) is a neural network algorithm which is especially suitable for the analysis and visualization of high-dimensional data. It maps nonlinear statistical relationships between high-dimensional input data into simple geometric relationships, usually on a two-dimensional grid. The mapping roughly preserves the most important topological and metric relationships of the original data elements and, thus, inherently clusters the data. SOM allows easy data fusion enabling visualization and analysis of large databases of rock blasting engineering. As a case study, the classification technique based on SOM has been used to classify the rock mass blastability rank. It can be founded from this paper that the SOM networks can be developed well based on a comprehensive data set of rock blasting engineering.

Jan 1, 2002

By Wm. Reisz, Raphael Trousselle

We are now well into our second decade of commercially available electronic initiation systems. Over this time, the technological advances have made electronic systems a very practical option for a wide variety of blasting applications.

Jan 1, 2011

By Dean E. Albon

The author gives a brief resume of his observations of drilling and blasting supervision in surface coal mines during the past thirty years and recommendations for upgrading this supervision to the category of a professional.

Jan 1, 1979

By Jean A. McIntyre

The Office of Surface Mining (OSM) has twice proposed rules for a blaster training and certification program to implement Sections 515(b)(15)(D) and 719 of the Surface Mining Control and Reclamation Act of 1977.

Jan 1, 1980

By Clive-Workman Davies, K K. Kabongo, Mensah Frimpong

Given the capital intensity of the dragline operation coupled with rising cost of explosives, the onus is on mine operators to make maximum use of explosives in blasting to assist dragline diggability. At a surface coal mine in South Africa large boulders necessitating secondary breakage and in some cases completely unfragmented sections of a blast resulting in low dragline diggability were encountered in the interburden blast. Twelve blasts were therefore closely monitored and dragline productivity evaluated. The ultimate aim was to improve the overall blasting performance and hence increase dragline productivity. Three areas were in focus; fragmentation assessment, dragline productivity assessment and cost analysis. The studies indicated unsatisfactory explosive and initiation performance, problematic blast design and questionable operators performance. It is established that dragline cost account for 60% of the total mining cost whereas the drilling and blasting cost account for the remaining 40% and that improvement in dragline productivity results in automatic cost saving.

Jan 1, 1996

By N K. Jain, Rajesh Jain

This article has been written indicating the present trend in Blasting all over the World, so as to help in planning production and development of Industrial Explosives for the development of industries in all the countries in general

Jan 1, 1992

By Wiliam Reisz

As we approach the peak season for thunderstorm activity it’s important to keep in mind that lightning still poses a serious threat to drilling and blasting operations. Lightning remains the number one cause of accidental detonation of explosives.

Jan 1, 2008

By Larry R. Fletcher

Excessive flyrock, which is blasted rock that travels beyond the secured blast area, is responsible for 25 pct of the blasting injuries that occur in surface mining. Excessive flyrock is also a frequent cause of damage to mine equipment and facilities.

Jan 1, 1986

By B. K. Rath

The Industrialization of a country depends on its mining activities to a great extent. In mineral production, India has a top rank not only in South Asia, at the global level too. Quantum of mineral production is almost directly proportional to the quantum of explosive production. Mining sector consume more than 80% of country’s explosive production. Due to rapid growth of mining activities in the country, the explosives industry has been developing very fast in terms of quantity, quality and types. , In this paper, India’s post independent chronological date regarding use of explosives, their types, their constraints and a profile of well-known manufacturers has been meticulously presented. A production figure for three years with system analysis has been presented. The paper also deals with present consumption pattern while making a futuristic forecast. In view of the anticipated changes that are to take place in mining industries in near future, the manufacturers of explosives have to pay a vital role. The paper highlights some concrete and valuable suggestions and recommendations. Small scale Companies have to limit their production to Slurry and Emulsion types of Cartridged explosives whereas the large manufacturing units have to concentrate on Bulk explosives, specialized explosives and better initiating systems. The large manufacturing units have also to make all concerted efforts to compete with global market for significant export. The Country for its rapid growth needs basic raw materials like Coal, Iron Ore and Limestone. So, the extraction of these minerals is of prime importance. The more we produce and consume, the more will be Industrialization. The Industrial growth rate has been around 6% during the last few years. As the Industrial growth rate is moderate, there is moderate increase in mineral extraction in the Country. Additional mineral extraction demands additional explosive production (Annexure-1).

Jan 1, 2000