Convergence behaviour - Packing relations of full extraction gate roadways at OAL lignite mine


CIM BULLETIN, vol.90, no.1013, pp.56-61, 1997 (Peer-Reviewed Journal) identifier identifier

  • Publication Type: Article / Article
  • Volume: 90 Issue: 1013
  • Publication Date: 1997
  • Journal Name: CIM BULLETIN
  • Journal Indexes: Science Citation Index Expanded, Scopus
  • Page Numbers: pp.56-61


This paper describes the results of convergence measurements conducted about five years for the re-use gate roadways at OAL lignite mine in Turkey. Double lignite seams separated with a marn layer, are mined with longwall retreating mining system at the mine. Rib pillar has been abandoned and gate roadways were planned to be packed for the re-use of full extraction. Various packing systems have been attempted, namely three rows of wooden chock, one row of wooden chock plus concrete wall and concrete wall only. The re-use of main gate roadways packed with wooden chock yielded 62% of closure. Lastly developed concrete packing of 3 meters wide and specially developed support set composed of three friction props and a cap, which is a modification of yieldable set, have successfully maintained the main and tail gate roadways stability with a total vertical convergence of 32%. Good correlation has been established between pack stiffness and floor heave as well as maingate and tailgate convergences. The elimination of rib pillars by re-use of gate roadways increased the coal recovery by 20% and decreased the development/production ratio from 0.065 m(3)/ton to 0.022 m(3)/ton.