Design Procedure for Arch Canopies for Rehabilitation of High-Roof-Fall Areas

Allwes, Richard A.
Organization: International Conference on Ground Control in Mining
Pages: 11
Publication Date: Jan 1, 1986
A procedure is presented for the design of an arch canopy for the application of rehabilitating a high-roof-fall area. This procedure is specifically developed for evaluating an unbackfllled arch canopy, which Is subjected to an impact load (roof fall). Dynamic line loading of the arch canopy at its crown is only considered and the procedure does not account for an unsymmetrical loading condition. The evaluation of whether an arch canopy is suitable for a particular installation is dependent upon many variables, including in-nine conditions and the engineering properties of the structure. However, a general evaluation can be based upon a comparison of the arch's maximum crown deflection and a prescribed allowable crown deflection. A single spring-mass system is used as an idealized model to represent the dynamic behavior of the arch canopy at its crown. An energy approach is taken to determine the maximum crown deflection of an arch rather than solving a differential equation of notion derived from dynamic equilibrium. The design procedure is based on the concept that when an arch canopy is subjected to impact loading at its crown and deflects from its unloaded state to maximum crown deflection, the structure absorbs strain energy, both elastic and plastic. As a result, this strain energy can be calculated from a static load-displacement diagram for the structure. The significance of this design procedure Is that It gives mine personnel an analytical tool to select an arch canopy to meet the dimensional and functional requirements of a mine entry and a prescribed allowable crown deflection.
Full Article Download:
(2501 kb)

Additional chapters/articles from the SME-ICGCM book Proceeding of the Fifth Conference on Ground Control in Mining (ICGCM)

Expanded Cement: New Solutions for Age-Old Problems
Determination of Effective Column Lengths for Resin-Grouted
How to Design an Efficient Roof Bolting Plan Based on Simple
Donut Cribbing--A Hew Heavy-Duty Roof Support Concept
Development of A Yielding Steel Post
Design Procedure for Arch Canopies for Rehabilitation of Hig
Investigation of Some Alternatives to Timber Posts and Cribs
Design and Field Testing of a Mobile Roof Support for Retrea
Change in Primary Roof Support System at Quarto Mining Compa
Remote Mining Using Water for Ground Support
New Type of Load Cell for Monitoring of Roof Bolt Tension
Field Measurements of Chain Pillar Response to Longwall Abut
Integrated Instrumentation Method of Stress State, Material
A Study of Roof Caving in the Eastern U.S. Coalfields
A Simple Tool to Measure Stress in Mine Backfill
Optimization of the Stress Control Method to Improve Product
Effect of High Horizontal Stress on Coal Mine Entry Intersec
Analysis of Small-Scale Thrust Faults and Their Effect on Co
A Case History of Computer-Aided Lineament Analysis for Grou
Designing for Upper Seam Stability in Multiple Seam Mining
Behavioral Aspects of Roof/Rib Injuries--Implications for Tr
Engineering Classification of Shales
Empirical Approach to Calculate Rock Loads in Coal Mine Road
Assessment of the Rockburst Proneness in Hard Rock Coal Mine
Outburst Control in Underground Coal Mines,
The Effect of Immediate Strata on Pillar Behavior in Retreat
Roof Control Problems on Development and Longwall Gateroads
A Case Study of Longwall Roof-Supports Interaction
Tailgate Support Evaluation at Plateau Mining Company
Methods of Controlling Hard Roof in a Longwall Face