(PDF) Influence of boundary conditions in DEM models of sublevel …

Ring wide model show greater ore dilution and lower recovery, while half wide models show the opposite results. Cumulative dilution differs for 10%, while ore recoveries differ in approximately 15 ...

Gravity flow research at the Kiruna sublevel caving mine …

In the past focus was on a specific hang-up type, see Figure 3. The actual hang-up evolves from an obstruction in the upper part of the extracted SLC ring caused by either incomplete breakage or clogging of the flow zone during the extraction. Such 'frozen' hang-up situations, in which a temporarily stable

Understanding the flow of caved ore and its influence on …

The development of the theory of free flow of granular materials in bins and hoppers into the Ellipsoid of draw theory in block caving and sublevel cave mine by Janelid and Kvapil (1966). This theory was based on 2D observations of draw in sand models with a Perspex front. The development of the interactive draw theory based on numerous tests ...

6.8: Quantum-Mechanical Orbitals and Electron …

Figure 6.8.5 6.8. 5: Electrons are added to atomic orbitals in order from low energy (bottom of the graph) to high (top of the graph) according to the Aufbau principle. Principle energy levels are color coded, while sublevels are grouped together and each circle represents an orbital capable of holding two electrons.

(PDF) Dumping oversize rock fragments in orepasses: the …

PDF | On May 27, 2023, Sohail Manzoor and others published Dumping oversize rock fragments in orepasses: the impact on the production cycle of a sublevel caving operation | Find, read and cite all ...

Design & Operating Principles in Caving Methods

DEFINITION: A mining method which is applicable to low grade near-vertical metallic or nonmetallic deposits. Mining progresses downwards while the ore between sublevels is broken overhand with long hole uppers (fan-holes). The overlying waste rock (hangingwall or capping) caves into the void created as the ore is drawn off.

Sublevel Caving Method Without Sill Pillar | SpringerLink

Then stopping proceeds with step-by-step blasting method. A caving overlying rock layer equal to 1.5–2 times the sublevel height must be maintained in the upper part of the stopping sublevel. Equipment shafts or ramps are arranged at a certain interval along the strike, in order to deliver equipment, materials, and personnel to the …

7.3: Quantum-Mechanical Orbitals and Electron Configurations

Figure 7.3.5 7.3. 5: Electrons are added to atomic orbitals in order from low energy (bottom of the graph) to high (top of the graph) according to the Aufbau principle. Principle energy levels are color coded, while sublevels are grouped together and each circle represents an orbital capable of holding two electrons.

Development of a model for economic control of …

Sublevel caving (SLC) is a mass mining method in which the ore is drilled and blasted while the waste rock caves and fills the space created by the extraction of ore (Cokayne 1982). The ore body is divided into vertical intervals called sublevel intervals. The ore within each sublevel interval is drilled in a fan-shaped

(PDF) Influence of boundary conditions in DEM models of sublevel …

Using DEM for the modeling of sublevel caving it is possible to estimate the outcome of the production for the known mining conditions. Herein, comparison of two different modelling approaches is presented. Comparing the two modeling approaches in DEM modelling of the sublevel caving process it was shown that fundamental differences exists.

Optimum Sublevel Height and Drift Spacing in Sublevel …

Weak rock mass and poor flow of material can cause excessive ore loss and dilution in sublevel caving. This paper proposes a method to establish design parameters for an inclined deposit within a weak rock mass and evaluates its effectiveness through a case study. In order to solve the problem of low production capacity and poor safety …

Failure of hanging roofs in sublevel caving by shock collision …

Hanging roofs or high hang-ups, a common problem in sublevel caving mining, usually result in a large ore loss and undermine mining safety. This paper …

Factors Influencing Stope Hanging Wall Stability and Ore …

Sublevel open stoping is commonly practiced in Canadian mines to extract steeply dipping narrow vein deposits, for example at Bousquet 2 mine in Quebec. This method is suited to mine out low-grade orebodies; ore recovery can reach 95–97% and ore dilution is only 5–10% (Abdellah et al. 2019 ; Sari and Kumral 2019 ; Ran 2019 ; Emad et …

(PDF) Development of an optimal draw control strategy for a sublevel …

The main contribution of this study is the incorporation of the uncertainty of delays from hang-ups and grades directly into the production scheduling process of a cave mining operation.

A global review of recovery, dilution and draw control in …

Figure 3 The location of sublevel caving mines included in the global review The type of production ring design and cut-off methodology (i.e. grade-based or tonnage-based draw limits) differs from mine to mine. Kiruna and Malmberget implement a silo shaped blast design, while all of the other mines use a fan pattern for production blast rings.

(PDF) Draw control strategies in sublevel caving …

The sublevel interval in the mine varies from 20 to 30 m depending on the size and shape of the orebody whereas the drift spacing is fixed at 22.5 m for all the orebodies. 6 The test was...

Sublevel Caving | PDF | Mining

Sublevel Caving. 13/01/2020 Applicability I *Sublevel caving is a mass mining method based on utilization of gravity flow of blasted ore & caved waste rock. *Sublevel is a high production, bulk mining method. *Sublevel caving is a caving method, causing subsidence at surface. *Sublevel caving is typically deployed under ground method, when surface …

3D mapping of sublevel caving (SLC) blast rings and ore …

Figure 1: (Left) Survey at a drawpoint in SLC crosscut, hang-up situation. Figure 2: (Right) Measurement procedure on-site, opening situation (not to scale). An application of the equipment for the survey of a hang-up is shown in Figure 1 and the measurement procedure in Figure 2. A single image pair yields a partial 3D model of the breakage face.

8.3.2: Shrinkage Stoping | GEOG 000

8.3.2: Shrinkage Stoping. Shrinkage stoping is a vertical stoping method, conducted in a vertical or near-vertical plane, and at an angle greater than the angle of repose of the broken ore. A defining characteristic of shrinkage stoping is that most of the blasted (broken) ore remains in the stope to support the hanging wall and footwall. However, when ore is …

(PDF) Longwall; Sublevel Caving and Block Caving …

PDF | Longwall Longwall in coal Longwall in Hard Rock Sublevel Caving Characteristics of the ore body and mining method …

(PDF) Rock fragmentation variations with increasing …

Rock fragmentation is vital in a sublevel caving operation. The oversize fragments are the most undesired fragmentation category because of their challenges; as such, they require special attention.

(PDF) Production scheduling optimisation for …

Download Free PDF. Production scheduling optimisation for sublevel stoping mines using mathematical programming: A review of literature and future directions ... The main contribution of this study is the …

Mathematical Programming Application in Sublevel …

the drawpoint make the sublevel caving method unique when producing a holistic plan. This paper reviews all mathematical programming models presented in …

Australian Centre for Geomechanics | Caving 2018

Caving 2018: Proceedings of the Fourth International Symposium on Block and Sublevel Caving, Caving 2018. 2018. Cuello, D; Newcombe, G. Key geotechnical knowledge and practical mine planning guidelines in deep, high-stress, hard rock conditions for block and panel cave mining.

Backfill Practices for Sublevel Stoping System

Sublevel stoping mining methods are very popular in Canadian metal mines since they enable maximum ore recovery due to pillar-less mining. Sublevel stoping mining …

9.6: Quantum-Mechanical Orbitals and Electron Configurations

Video (PageIndex {1}): Energy levels, sublevels and orbitals. Nitrogen has 7 electrons. Write the electron configuration for nitrogen. Take a close look at Figure (PageIndex {5}), and use it to figure out how many electrons go into each sublevel, and also the order in which the different sublevels get filled.

Rock fragmentation variations with increasing extraction …

1. Introduction. Sublevel caving (SLC) is a large-scale mining method primarily used in orebodies with steep dip and large vertical dimensions [Citation 1].As in other caving methods, the function and efficiency of SLC depends on the properties of the orebody and the overlying waste rock [Citation 1].The blastholes are drilled upwards, in …

A global review of recovery, dilution and draw control in …

A total of 21 mines spread over four continents and 17 different mining companies participated in the study. This paper describes the main findings of the study related to …

Lesson 2 Newton's Laws chapter at The Physics …

4. A skydiver (who hasn't opened his parachute yet) falls at terminal velocity. Consider the forces acting on the skydiver. 5. A block rests on top of a table. Consider only the forces acting upon the block. 6. A block is being pushed across the top of a table. Consider only the forces acting upon the block.

Numerical analyses of the hangingwall failure due to …

The sublevel caving used in Kiirunavaara mine induces failure and subsidence of the hangingwall. Two sections of the mine were studied by means of …

The influence of drawbell geometry on hang-ups during ore …

In underground mining, hang-ups due to coarse fragmentation are frequently observed in drawpoints, drawbells, and ore passes during ore draw. Hang-ups can often require operational interference and hang-up removal activities. Drawpoint and drawbell design has been shown in some studies to influence hang-ups; however, the full extent …

(PDF) Draw control strategies in sublevel caving mines

The sublevel interval in the mine varies from 20 to 30 m depending on the size and shape of the orebody whereas the drift spacing is fixed at 22.5 m for all the orebodies. ...

Underground Mining Methods and Equipment

methods and brief explanations of the techniques of room-and-pillar mining, sublevel stoping, cut-and-fill, longwall mining, sublevel caving, and block caving. The second section describes underground mining equipment, with particular focus on excavation machinery such as boomheaders, coal cutters, continuous miners and shearers. 1.

Abstract arXiv:2210.16940v4 [cs.LG] 22 Dec 2023

1): V(η) ≤cfor some constant c, which is known as a Lyapunov sublevel set. Once a state enters a Lyapunov sublevel set it remains there for all time. The potential function depicted in Figure1can be viewed as a Lyapunov function, and the yellow line the boundary of the corresponding sublevel set.