Roof Movement and Failure Behavior When Mining Extra-Thick Coal Seams Using Upward Slicing Longwall-Roadway Cemented Backfill Technology

Figure 1

The technical principles of USLCB [14]. (1) Haulage rise; (2): rail rise; (3) headgate; (4) tailgate; (5) boundary crosscut; (6) mining working face; (7) backfilling working face; (8) backfilled body.