Research Article

A Control Approach of the Roof in No-Pillar Roadway Formed by Roof Cutting and Pressure Releasing

Table 1

Criteria for judging roadway roof state.

State of rock beamFixed two end beamCritical stateSimply supported beamCritical stateFailure

tt < tgt = tgtg < t < tzt = tzt > tz
ωω < ωgω = ωgωg < ω < ωzω = ωzω > ωz