1 / 30

REFLECTIONS ON 30 YEARS IN GROUND CONTROL

REFLECTIONS ON 30 YEARS IN GROUND CONTROL. 6 2010. Analysis of Retreat Mining Pillar Stability (ARMPS): Version 6 (2010). L s. L b. c4. c1. D. A. c3. c2. W s. C. We could spend a million dollars trying to explain why this intersection collapsed….

stewart-velazquez
Download Presentation

REFLECTIONS ON 30 YEARS IN GROUND CONTROL

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. REFLECTIONS ON 30 YEARS IN GROUND CONTROL

  2. 6 2010 Analysis of Retreat Mining Pillar Stability (ARMPS): Version 6 (2010)

  3. Ls Lb c4 c1 D A c3 c2 Ws C

  4. We could spend a million dollars trying to explain why this intersection collapsed…

  5. But then how do we explain the 100 nearby “just like it” that stayed up??!!

  6. Other engineers have accurate knowledge of material properties and applied loads.

  7. Because rock mass behavior is so complex, we need a different approach.

  8. From a practical standpoint, maybe its “good enough” to know that the odds of failure were 1-in-100.

  9. EMPIRICAL METHODS Make use of knowledge gained during “full scale testing” of mine designs.

  10. Empirical methods focus on the success or failure of the full scale design.

  11. Require a simplified model that includes all the important factors.

  12. TAILGATE ENTRY STABILITY

  13. Empirical design guidelines are closely linked to reality, easy to understand, and easy to use.

  14. Analysis of Retreat Mining Pillar Stability (ARMPS) Analysis of Multiple Seam Stability (AMSS)

  15. SYNERGY WITH NUMERICAL MODELS

  16. Safety During Pillar Recovery: A Ground Control Success Story

  17. Fatal Roof Falls During Retreat Mining 1995-2005

  18. Fatal Roof Falls During Retreat Mining 1995-2011 One fatal roof fall in six years

  19. Use extra roof bolt support Mobile Roof Supports Leave the final stump Technologies that made the difference

  20. Retreat Mining ~ 30 million tons/year ~ 400 tons/pillar ~ 80,000 pillars/year ~ 200 retreat mines ~ 400 pillars/mine/year

  21. Retreat Mining ~ 80,000 pillars/year ~ 400 pillars/mine/year Prior to 2005, nationwide there were ~ 2 fatals/year ~ Rate was 1 fatal/40,000 pillars Typical mine: One fatal every 100 years

  22. CRANDALLCANYONMINE DISASTER

More Related