Underground chamber roof cavity filling system - inserts empty sack and fills with hardening material

摘要

The system supports and fills up roof cavities in underground chambers so as to arrest falling rock. An empty sack is inserted in the cavity, and then filled with hardening material. The sack can be brought into the hole above a shield from below, and two-ingredient plastic can be injected into it. It can comprise sheets glued together of low-pressure polyethylene and stretched in different directions. A filler opening and vent holes can be included in it.