Design Considerations of the Secondary Roof Support for Longwall Tailgate Entries

Chen, Jinsheng
Organization: International Conference on Ground Control in Mining
Pages: 6
Publication Date: Jan 1, 2003
To maintain the stability of longwall tailgate entries, they have to be supported by not only the primary roof support but also the secondary roof support due to the impact of the longwall mining┬Činduced abutment loads. Depending on the mining condition of a typical coal seam and its distance from the previous panel's gob, the longwall tailgate entry is often reinforced by the secondary roof support in the form of standing supports and/or cable bolts or trusses during longwall retreat, Even though lots of research work has been done to study the behavior of different standing supports in the laboratory. their function and requirements for a typical mining condition are still not fully understood due to lack of field data and correct assumptions about the behavior of the already-bolted entry roof under mining-induced abutment loads. Therefore, the application of the secondary roof support for tailgate entry roof control is still limited to trial and error, which often results in either higher cost for tailgate roof control if the design is too conservative or more production delays due to roof falls in the outby tailgate entry if the design is inadequate. To have a better tailgate roof control with reasonable roof control cost, RAG American Coal, NIOSH, and HeiTech have been conducting a joint research project to monitor actual roof loading, roof deformation, and entry convergence in the tailgate entry of 10 North panel at RAG Emerald mine. The actual roof loading data are used to calibrate and improve the roof control model for longwall tailgate entries, which has been developed by RAG American Coal, and to further reduce the roof control cost for longwall tailgate entries. The authors in this study attempt to discuss the Roof Control Model developed by RAG American Coal. in which some guidelines or important parameters for designing the secondary roof support for longwall tailgate entries are proposed.
Full Article Download:
(1756 kb)


Additional chapters/articles from the SME-ICGCM book 22nd International Conference on Ground Control in Mining (ICGCM) 22nd

Pillar Design and Roof Support for Controlling Longwall Head
Stress Analysis and Support Design for Longwall Mine-Through
The Utilisation of Numerical Modelling to Predict Water and
Longwall Roof Fall Prediction and Shield Support Recommendat
Comparison Of Multiple And Single Entry Roadways For Highly
Numerical Modeling Of Longwalls In Deep Coal Mines
The Characteristics Of Mining-Induced Fractures In Overlying
Design And Experience Of Total Extraction Room And Pillar Op
Using Site Case Histories Of Multiple Seam Coal Mining To Ad
Mining Method For Extracting An Eight Metre Coal Horizon Con
Stooping Low Safety Factor Pillars At Goedehoop Colliery
Modelling Of Pillar Stability In Room And Pillar Mines
Pillar Optimization For Initial Design And Retreat Recovery
Application Of RMT's Remote Reading Telltale System To
Rock Mechanics Study Of Lateral Destressing For The Advance-
New Tools For Roof Support Evaluation And Design
Considerations For Using Roof Monitors In Underground Limest
Mine Roof Geology Information System (MRGIS)
Imaging Ahead Of Mining With Radio Imaging Method (RIM-IV) I
Geophysics For The Detection Of Abandoned Mine Workings
Investigation Of Seam Thickness And Seam Splitting Within A
Determination Of Rock Strength Properties Using Geophysical
RQD from the Barrel to the Box: Weatherability May be a Bett
A probabilistic approach to ground support design in undergr
The Requirements of a Database to Store Geotechnical Data to
Variation of Horizontal Stresses and Strains in Mines in Bed
Geotechnical Planning Basis for the Optimization of Workings
Tensile roof failure arising from horizontal compressive str
Study of load transfer capacity of bolts using short encapsu
Intersection Stability and Tensioned Bolting
Premature Rock Bolt Failure Through Stress Corrosion Crackin
Short-encapsulation Pull Tests for Roof Bolt Evaluation at a
Field Test with Strain-gauged Friction Bolts at the Gold Hun
Directional Rock Bolt Pullout Tests as Index Tests for Estim
Eclipse Bolting System
The Application of Pre-tensioned Grouted Tendons at Harworth
Investigation into the Extent and Mechanisms of Gloving and
Developments in Improving the Standard of Installation and B
Development of Geotechnical Procedures for the Analysis of M
Recent Developments in the Use of Seismic Tomography in Long
Pumpable Roof Supports: Developing Design Criteria by Measur
Design Considerations of the Secondary Roof Support for Long
The Effect of Standing Support Stiffness on Primary and Seco
Numerical Modeling of the U1A Complex at the Nevada Test Sit
Rock Mechanics and the Analysis of Underground Mine Stabilit
A Study of Potential Fault Reactivation and Water Intrusion
The Elimination of Rock-fall Fatalities in Ontario Hardrock
Root Causes of Groundfall Related Incidents in U.S. Mining I
Analysis on the Dynamics of Mining Subsidence in Range of a
Mitigating Subsidence Influences on Residential Structures C
Influences of Longwall Subsidence on a Guyed Steel Tower - A
Surface Movement of Super-wide Longwall Panels Using Top-coa
New Approach to Evaluate the Stability of Yield Pillars
Experimental Study of Acoustic Emission Characteristics for