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PDF | Shrinkage stoping Ascending method of mining Advantages and Disadvantages Vertical Crater Retreat stoping Introduction Application Developmental... | Find, read and cite all the...
In the previous work reporting the results of preliminary study, method of vertical crater retreat (VCR) multiple-deck shots with different and smaller slice heights was used to excavate the raise in one blast. ... VCR drop-raising is actually an offshoot of vertical crater retreat (VCR) mining method based on Livingston's cratering theory. 8 ...
The blasting test on the vertical crater retreat mining method and the blasting vibration were analyzed. It is estimated if the vibration damage possibly the surface buildings and …
crater blasting: used in the vertical Crater Retreat (VCR) mining method; cast blasting: adaptation of bench blasting used in certain area surface applications, predominantly in the Powder River Basin surface coal mines. In past lessons, we've defined some key terms for the design of a blast round. By way of review, these included the following:
November 2002 · The Israel Medical Association journal. Head louse infestations are prevalent worldwide. Over the past 20-25 years, 15-20% of all children in Israel between 4 and 13 years of age ...
This presentation will compare various methods of developing these Slot Raises and introduce two new ones. The author begins with a short discussion on the mining method, and its variations, where Slot Raises are used. This mining method is called Vertical Crater Retreat or VCR which is a blasting method based on spherical …
The method progresses vertically, as successive slices of ore are detonated. Vertical Crater Retreat (VCR) uses parallel, vertical, descending and spherical concentrated loads to fragment the ore (disassemble by cratering) drilling; The advance of the stope is disassemble from the bottom up; The ore is recovered at the bottom of the block; Part ...
Keywords Iron mine Vertical crater retreat mining method (VCR) Blasting test Vibration monitoring 1 Introduction The initial design scheme of the Luohe iron mine was sub-level caving mining. In the collapse area, the requisition of lands were 2940 acres and the resettle-ment were about 3–4 villages. After 4 years of
Vertical crater retreat (VCR) mining is a method originally developed by the Canadian. mining company INCO. Today, VCR is an established mining method used by mines all over the world that. have competent, steeply dipping ore and host rock. VCR is based on the crater blasting technique in which powerful explosive charges are.
The paper reviews the history of vertical crater retreat mining, various methods of applying vertical crater retreat layouts, the development of in-the-hole drills …
Crater Retreat mi n i ng method a potential alternative. Visits were made to a number of North Ameri can mi nes in an effort to determi ne various parameters for implementing the method. VCR Method This mining method uses spherical charges as aga i nst col umn charges3,4,5,6 used inmost other methods of stoping.
This method is called vertical crater retreat (VCR) or vertical retreat mining (VRM) method. VCR method has been an established mining method being practiced in various mines all over the world. 8 An offshoot of this mining method is the VCR drop-raising technique that employs the same spherical crater charge technology as VCR …
Vertical Crater Retreat is compared to other open stoping methods. Various geotechnical factors have been considered including the effects of stress concentration, jointing, dynamic stresses superimposed by blasting vibrations, amount of development required and shrinkage draw. All these factors favour a VCR method in a deep mining environment.
A blasting method employed in underground sublevel mining. Initially a vertical slot extending across the width of the stope is mined. The remaining portion of the stope is then blasted by section into the vertical slot following sublevel procedures. Ref: SME, 1 ii. A variation of the sublevel stoping method that uses basic crater blasting models.
The vertical crater retreat mining method is also known as VCR mining. This mining method precipitously dips strata for mineralization. This method blasts rocks with total and heavy charges with a large diameter of 165 mm. VCR's blasting creates a cone-shaped opening in the targeted rock mass to let the materials be mined quickly. The …
When the criteria are evaluated with the alternatives, the mining method with the highest score of 18% was found to be Vertical Crater Retreat (VCR) followed by Sublevel Open Stoping with 16.62%.From the sensitivity analysis, rankings did not change as the variables were altered by 1 to 6% and 5 to 25%.The Vertical crater Retreat still remains ...
cratering theory. This method is called vertical crater retreat (VCR) or vertical retreat mining (VRM) method. VCR method has been an established mining method being practiced in various mines all over the world [8]. An offshoot of this mining method is the VCR drop-raising technique that employs the same spherical crater charge technology …
On the other hand, several blasting technique innovations have also improved the raising safety. In Canada in 1975, mining company INCO developed a mining …
The name of this method derives from this drawing off or shrinkage of the stope. A modern and important variant of this method is known as vertical crater retreat (VCR) mining. A few examples of commodities mined by this method include iron and palladium. Watch this video (3:01) created by demonstrating sublevel stoping mining method.
A scheme of multiple deck blasting based on vertical crater retreat (VCR) drop-raising method was designed for an abandoned cavity with 30-m cover. The lower …
Vertical Crater Retreat: an Important New Mining Method L.C. LANG INTRODUC'I'ION The introduction of 165-mm (6% -in.) holes to underground mining operations has made possible the application of Canadian Industries Ltd's (CIL) vertical crater retreat (VCR) mining method, illustrated in the accompanying sketches. This unique and revolutionary …
Keywords: underground mining, sublevel stoping, mine backfill, cemented rockfill. 1 Introduction Many Canadian metal mines have adopted sublevel stoping method or one of its variations, such as blasthole stoping, vertical crater retreat (VCR), or vertical block mining (VBM) for the extraction of steeply dipping ore bodies [1]. In these
Vertical Crater Retreat is compared to other open stoping methods. Various geotechnical factors have been considered including the effects of stress concentration, jointing, …
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The mining method currently in use is the mechanised up-dip Vertical Crater Retreat (VCR) with waste rock as post-fill. Figure 2: Mindola Sub-Vertical Mine General Layout of Mining Method showing VCR chamber excavations (Mopani Copper Mines - Mindola Mine Planning Depart - ment, Report, 2014).
Vertical crater retreat (VCR) mining is a method originally developed by the Canadian mining company INCO. Today, VCR is an established mining method used by mines …
3. DROP RAISING - INTRODUCTION Special method of charging of Explosives and blasting is done in stages from bottom level for excavation in slices. The charging and blasting of the holes is based on Vertical Crater Retreat (VCR) method. The raise is driven either vertically or with steeply inclined dip. Mucking of blasted material …
1. Introduction. VCR (vertical crater retreat) mining technology is widely used in mine engineering because it possesses many better features, such as higher efficiency and more simple operation. In the mining process, the blasting shock originating simultaneously from the rock-fracturing blasting load also can damage surrounding rock. …
The most commonly used sublevel stoping mining methods are sublevel open stoping, long-hole open stoping, and vertical crater retreat (VCR). It is applicable to large, steeply dipping, regular competent ore bodies surrounded by competent host rock in both the hanging wall and the footwall.
Download scientific diagram | -Vertical crater retreat mining method (, 2007) from publication: Possibility of application of backfill methods with cementing fill in ore body Borska ...
This course refers to the generic mining method of sublevel stoping. The most commonly used sublevel stoping mining methods are sublevel open stoping, long-hole open stoping or blasthole stoping, and vertical crater retreat (VCR). Variations of this method include vein (Alimak) mining, transverse stoping, Avoca and longitudinal …
5) Shrink age Stoping. Shrinkage stoping may be termed a " classic" mining method, having been perhaps the most popular mining. method for mos t of the past century. It has largely been ...
