the design of pillars in the shrinkage stoping of a

the design of pillars in the shrinkage stoping of a

The design of pillars in the shrinkage stoping of a

It was found that a stress level of 70 MPa for the width of combined pillars (Le. crown and sill pillars) causes failure of the reef drives as well as the tops and bottoms of the stope side walls. As shrinkage stoping to depths of more than 650 m would result in very Iow percentage extractions, alternative methods of stoping will have to be ...

Design methods for stopes and sill pillars with ...

The design of pillars in cut-and-fill mining and open stoping in vertical and subvertical orebodies is of vital importance in optimizing mining operations. The primary requirement for a good and reliable design technique is the ability to represent the actual physical behaviour of the pillar. In this paper, a new methodology for stope roof and sill pillar design is proposed for the Zinkgruvan ...

Shrinkage stoping - QueensMineDesignWiki

2019-6-28  Shrinkage stoping is a mining method used for steeply dipping, narrower ore bodies with self supporting walls and ore. It is an overhand mining method that relies on broken ore being left in the stope to be used as the “working floor” and to support the walls.

Shrinkage Stoping - Oraee

2016-9-19  Merits of shrinkage stoping. Merits of the method have to be compared with other methods applicable in similar conditions, i.e. sublevel stoping and cut-and-fill. Shrinkage is unique in that at least 2/3 of the output is tied up in the stope. This can be an important economic disadvantage.

Compare Stoping Methods of Mining

2017-4-5  On the whole, however, shrinkage stoping as usually practiced permits the starting of stopes soon after the drifts have entered the ore. As only about 35 to 40 percent of the ore broken is available until completion of a stope, more stopes are

[PDF] Determination of the Optimum Crown Pillar

In this paper, a relationship between dependant parameters and the crown pillar thickness is first introduced. This relationship defines geotechnical problems caused by thin pillars and economic considerations created by pillars that are thicker than the optimum size. For this purpose, a dimensional analysis as an effective physico-mathematical tool was used.

(PDF) Rib pillar design in open stope mining

1989-6-1  The approach involves an empirical method for pillar design and a discusion of the pillar stability used for open stope mining methods. The empirical method predicts the stability of rib pillars.

Chapter

2020-6-11  the roof; the pillars may or may not be removed at a later time; 7) Shrinkage stoping - a stoping method in which most of the blasted ore is left to accumulate in the stope until the stope is completely mined. The broken ore is then drawn off all at once. 8) Cut-and-fill - a stoping

Longitudinal longhole retreat - QueensMineDesignWiki

2019-6-28  From Queen's University Mine Design Wiki Longitudinal longhole retreat is a branch of the generic mining method known as sublevel stoping. For longitudinal retreat the long axis of the stope is along (or parallel) to the strike of the orebody. It may also be referred to as bench stoping

[PDF] Pillar Design in the Hard Rock Mines of South

This paper gives an overview of the difficulties associated with the design of hard rock pillars in South African mines. Recent examples of large scale pillar collapses in South Africa suggest that these were caused by weak partings which traversed the pillars. Currently two different methods are used to determine the strength of pillars, namely, empirical equations derived from back analyses ...

Stoping Mining Methods - Metallurgist Mineral

2017-4-3  Shrinkage Stoping. In shrinkage stoping the ore is mined in successive flat or inclined slices, working upward from the level or the bottom of the block of ore. After each slice or cut, enough broken ore is drawn off from below to provide a working space between the top of the pile of broken ore and the back of the stope (fig. 88).

Chapter

2020-6-11  the roof; the pillars may or may not be removed at a later time; 7) Shrinkage stoping - a stoping method in which most of the blasted ore is left to accumulate in the stope until the stope is completely mined. The broken ore is then drawn off all at once. 8) Cut-and-fill - a stoping

Room and Pillar Stoping - Xinhai

Room and Pillar Stoping. Post pillars are reserved in the stope for support. According to the depth of blasting holes, there are two mining methods: short-hole room and pillar stoping; medium- and deep-hole room and pillar stoping.

12. Mining methods and method selection

2018-1-30  -Pillars are normally arranged in a regular grid array to simplify planning, design and operation.-Pillars may be permanently unmined or recovered in the orderly retreat from a mine panel.-Orebody must be relatively shallow to prevent commitment of excessive ore in pillars: orebodies of 6 m or greater height are worked by multiple passes.

A long hole stoping system for mining narrow platinum

2009-8-27  A long hole stoping system for mining narrow platinum reefs Sandvik. All relevant design perimeters of the area to be mined were taken into consideration. Production targets The following production targets were set: To optimize face advance (Target of 2 m per blast) 125 m drilled per single shift (5000 m per month on a double shift basis)

Compare Stoping Methods of Mining

2017-4-5  On the whole, however, shrinkage stoping as usually practiced permits the starting of stopes soon after the drifts have entered the ore. As only about 35 to 40 percent of the ore broken is available until completion of a stope, more stopes are required to produce a given tonnage at the beginning of operations than otherwise would be needed.

Geotechnical Design For Sublevel Open Stoping

2014-4-1  The first comprehensive work on one of the most important underground mining methods worldwide, Geotechnical Design for Sublevel Open Stoping presents topics according to the conventional sublevel stoping process used by most mining houses, in which a sublevel stoping geometry is chosen for a particular mining method, equipment availability, and work force experience.

8.3.3: Sublevel (Open) Stoping ABC 123: Testing Site ...

2010-8-3  8.3.3: Sublevel (Open) Stoping. If we had a stronger and more competent host rock, we could dispense with the need to keep ore in the stope to support the hanging wall as we do VCR mining. Indeed, such deposits do exist, and when they do, we can employ the open stoping method.

Hard-rock room and pillar - QueensMineDesignWiki

2019-6-28  To design pillars to a size where they are able to stabilize an opening without excessive ground support, a detailed geotechnical study should be carried out, documenting roof and ore strength, geological structures, joints and fractures (rock mass classification), and in-situ stress measurements.With these parameters, rock-mechanics engineers can anticipate pillar behaviour in

Room and Pillar Stoping - Xinhai

Room and Pillar Stoping. Post pillars are reserved in the stope for support. According to the depth of blasting holes, there are two mining methods: short-hole room and pillar stoping; medium- and deep-hole room and pillar stoping.

Underground Mining Methods and Equipment

2020-8-25  • Shrinkage stoping • Sublevel stoping Of the unsupported methods, room-and-pillar mining is employed for extraction of flat-dipping and tabular deposits, whereas shrinkage and sublevel stoping are applied to vertical or steeply inclined ore bodies. Shrinkage stoping has in the past been very popular, particularly in non-coal mining.

SECTION 10 SHRINKAGE METHODS Mike Turner

2006-7-8  Shrinkage mining was a common stoping method prior to mechanised mining and the introduction of hydraulic fill. Sub-level stoping, cut and fill mining and sub-level caving have generally replaced shrinkage mining in Australia, Europe and Canada. The method is still used in a handful of non-mechanised mines in South America, Africa, Asia and Canada.

Lesson 8.3: Mining by Unsupported Methods ABC

Shrinkage stoping is used to recover steeply dipping orebodies when the ore and host rock are reasonably competent. A stope, i.e., a large section of the mine where active production is occurring, is mined, but the broken ore is not removed, but rather is left in place to support the walls of the stope until the time when all of the broken ore ...

A long hole stoping system for mining narrow platinum

2009-8-27  A long hole stoping system for mining narrow platinum reefs Sandvik. All relevant design perimeters of the area to be mined were taken into consideration. Production targets The following production targets were set: To optimize face advance (Target of 2 m per blast) 125 m drilled per single shift (5000 m per month on a double shift basis)

Choice of Method

SHRINKAGE STOPING . The Sleeping Giant mine mainly uses the shrinkage stope method since a good selectivity can be obtained. _____ SEMI-SHRINKAGE STOPING . This method is generally used when the dip varies between 40 and 50 degrees. The mining is done like the shrinkage stoping. Given the gently dipping, the gravity sliding of the ore is difficult.

PDF Geotechnical Design For Sublevel Open Stoping

2014-4-1  The first comprehensive work on one of the most important underground mining methods worldwide, Geotechnical Design for Sublevel Open Stoping presents topics according to the conventional sublevel stoping process used by most mining houses, in which a sublevel stoping geometry is chosen for a particular mining method, equipment availability, and work force experience.

8.3.3: Sublevel (Open) Stoping ABC 123: Testing Site ...

2010-8-3  8.3.3: Sublevel (Open) Stoping. If we had a stronger and more competent host rock, we could dispense with the need to keep ore in the stope to support the hanging wall as we do VCR mining. Indeed, such deposits do exist, and when they do, we can employ the open stoping method.

Underground Mining Methods Handbook - Mining

Underground Mining Methods Handbook by W.A. Hustulid, Editor Society of Mining Engineers 1982 - 1794 Pages. General Mine Design Considerations

Sublevel stoping..Underground mining methods

2014-10-22  Sublevel stoping..Underground mining methods 1. Hassan Z. Harraz [email protected] 2014- 2015 This material is intended for use in lectures, presentations and as handouts to students, and is provided in Power point format so as to allow customization for the individual needs of course instructors.