Coal pillar structure

2020 ◽  
pp. 493-547
Author(s):  
M.L. Jeremic
Keyword(s):  
Coal Pillar ◽  
Pillar Structure

Coal Pillar Drawing Methods in Europe

1921 ◽  
Vol 3 (3supp) ◽  
pp. 284-284
Author(s):  
George S. Rice
Keyword(s):  
Coal Pillar

Adapting the European System of Financial Supervision (ESFS) to the EEA Two-Pillar Structure – A Workable Solution?

2019 ◽  
Vol 16 (5) ◽  
pp. 557-591
Author(s):  
Andri Fannar Bergþórsson
Keyword(s):  
Financial Crisis ◽  
Global Financial Crisis ◽  
National Level ◽  
Financial Supervision ◽  
Member States ◽  
Eu Member States ◽  
European System ◽  
Pillar Structure ◽  
The Global Financial Crisis ◽  
The Eu

In response to the global financial crisis, the European System of Financial Supervision (ESFS) was created in 2010. Supranational bodies were established for different financial sectors to act as supervisors of sorts for national-level supervisors in EU Member States. This article focuses on how the system was adapted to three EFTA States that are not part of the EU but form the internal market along with EU Member States through the EEA Agreement – Iceland, Norway and Lichtenstein (EEA EFTA States). The aim is to clarify how ESFS has been incorporated into the EEA agreement and to discuss whether this a workable solution for the EEA EFTA States that have not transferred their sovereignty by name in the same manner as the EU Member States. One issue is whether the adaptation has gone beyond the limits of the two-pillar structure, as all initiative and work stem from the EU supranational bodies and not the EFTA pillar.

scholarly journals Preliminary rib support requirements for solid coal ribs using a coal pillar rib rating (CPRR)

2020 ◽  
Author(s):  
Khaled Mohamed ◽  
Mark Van Dyke ◽  
Gamal Rashed ◽  
Morgan M. Sears ◽  
Robert Kimutis
Keyword(s):  
Coal Pillar ◽  
Solid Coal

scholarly journals Sub-Level Stoping in an Underground Limestone Quarry: An Analysis of the State of Stress in an Evolutionary Scenario

2016 ◽  
Vol 61 (1) ◽  
pp. 199-216 ◽  
Author(s):  
Marilena Cardu ◽  
Sergio Dipietromaria ◽  
Pierpaolo Oreste
Keyword(s):  
Numerical Models ◽  
The State ◽  
In Situ Tests ◽  
Future Scenario ◽  
Limestone Quarry ◽  
Geomechanical Properties ◽  
State Of Stress ◽  
Upper Level ◽  
Pillar Structure

Abstract The aim of this study was to evaluate the state of stress of a „voids-pillar“ structure excavated by means of the sub-level stoping method in an underground limestone quarry near Bergamo (Italy). Both the current structure of the quarry (i.e. the rooms exploited till now) and a possible future scenario were analysed using the (FDM) FLAC 2D code. The quarry has been in operation since 1927; at present, exploitation is carried out underground via the sub-level stoping method. Exploitation involves two levels, with 5 rooms on the upper level and 9 rooms on the lower level. After analysing data obtained from laboratory and in situ tests carried out on rock samples and natural discontinuities, the geomechanical properties of the medium, knowledge of which is essential in order to establish the parameters that must be included in the numerical model, were evaluated. The implementation of three numerical models made it possible to study both the present conditions of quarry exploitation and the evolution of the exploited rooms, as well as a possible expansion involving a third level of rooms. Using the results obtained regarding the stress-strain present in the pillars, a potential change in room geometry was proposed aimed at reducing the stress state inside the pillars, decreasing plasticity and increasing overall quarry safety.

The Intergovernmental Constitution of the EU's Foreign, Security & Defence Executive

2011 ◽  
Vol 7 (3) ◽  
pp. 453-480 ◽  
Author(s):  
Daniel Thym
Keyword(s):  
Security Policy ◽  
External Action ◽  
Foreign Affairs ◽  
Executive Order ◽  
Policy Changes ◽  
Defence Policy ◽  
Foreign And Security Policy ◽  
Pillar Structure ◽  
The Eu

European Union – Common Foreign and Security Policy – Changes with the abolition of the pillar structure by the Lisbon Treaty – Common Security and Defence Policy – Executive order of the EU – Between supranationalism and intergovernmentalism – The role of the High Representative – Joint political leadership – The European External Action Service as an administrative infrastructure – Constitutionalisation of foreign affairs

scholarly journals A Case Study of Damage Energy Analysis and an Early Warning by Microseismic Monitoring for Large Area Roof Caving in Shallow Depth Seams

2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Like Wei ◽  
Qingxin Qi ◽  
Hongyan Li ◽  
Bin Zhang ◽  
Yongren Wang ◽  
...  
Keyword(s):  
Early Warning ◽  
Damage Mechanics ◽  
Coal Pillar ◽  
Microseismic Monitoring ◽  
Energy Model ◽  
Field Application ◽  
Shallow Depth ◽  
Large Area ◽  
Cumulative Energy ◽  
Damage Level

Shallow depth coal seams are widely spread in Shendong mining area, which is located in the Northwestern region of China. When working face is advanced out of concentrated coal pillar in upper room and pillar goaf, strong strata behaviors often cause support crushing accidents, and potentially induce large area residual pillars instability and even wind blast disaster. In order to predict the precise time when the accident happens, guaranteeing life-safety of miner, microseismic monitoring system was for the first time applied in shallow coal seam. Based on damage mechanics correlation theory, the damage energy model is established to describe relationship between damage level and cumulative energy of microseismic events. According to microseismic monitoring data of two support crushing accidents, the damage energy model is verified and an effective early warning method of these accidents is proposed. The field application showed that the early warning method had avoided miners suffering from all support crushing accidents in Shigetai coal mine.

Principle of Well-Net Design for Coalbed Methane Exploitation in Coal Mine Area

2014 ◽  
Vol 543-547 ◽  
pp. 3967-3973
Author(s):  
Bao Shan Han
Keyword(s):  
Coal Mining ◽  
Coal Mine ◽  
Coalbed Methane ◽  
Design Theory ◽  
Surface Condition ◽  
Coal Pillar ◽  
Negative Influence ◽  
In Situ Stress ◽  
Well Location

There are abundant CBM (Coalbed Methane) in China. These CBM has caused a remarkable problem to the coal-mining in China. In order to improve the structure of Chinese energy and eliminate the risk of coal mine gas, the relevant industries and sections have implemented many explorations in CBM enriched areas. With great achievements, there are many important problems in the actions of CBM exploitation. The disadvantageous interaction of the surface CBM well and the later coal mining has been ignored at all. There are many disadvantages and defects. To solve these problems and eliminate or weaken the disadvantageous, the scientific and reasonable design of surface CBM well location is an important step. With the thinking of surface condition, coal mining plan, the arrangement of coal mine laneway, the direction and scale of the in-situ stress, and thinking more about the negative influence to and of surface CBM well, according to the theories of mining dynamics, mining engineering, mining geomechanics, and the CBM engineering, the design theory of the surface CBM well net can be studied. Finally, the arrangement principle of CBM product well in coal field is presented. The existing or future coal pillar will be a critical location for the surface CBM well location.

Sign in / Sign up

Export Citation Format

Share Document