Three-level prevention and control method for rock burst roadway
A three-level prevention and control method for a rock burst roadway, the method comprising: pre-weakening a thick and hard rock layer above a roadway before the roadway is excavated; carrying out prestress support, pressure relief and reinforcement when the roadway is excavated; and carrying out stress transfer on an advance abutment pressure, and arranging a composite energy absorption protective structure around the roadway before the mining of a working face. By coordinating the spatio-temporal relationship between pressure relief, support and prevention, the energy dissipation in the rock burst roadway is changed from an unstable, disorderly and uncontrollable dissipation state to a stable, orderly and controllable dissipation state.
1. A three-level prevention and control method for roadway rock burst, comprising:
before digging a roadway, pre-weakening a thick and hard rock stratum above the roadway using a regional staged hydraulic fracturing technology of long borehole;
during digging the roadway, performing a pre-stress support, a pressure relief, and a reinforcement; and
before stoping at working-face, transferring a stress of an advanced abutment pressure using a local hydraulic fracturing technology of medium and short borehole, and arranging a composite energy-absorbing protective structure around the roadway.
2. The three-level prevention and control method for roadway rock burst according to claim 1 , wherein during digging the roadway, the pre-stress support is performed by using a bolt rod and/or a bolt cable, the pressure relief is performed by casing drilling and the reinforcement is performed by grouting.
3. The three-level prevention and control method for roadway rock burst according to claim 1 , wherein the arranging the composite energy-absorbing protective structure around the roadway comprises: arranging a protective support in the roadway and filling a buffer energy-absorbing cushion between the protective support and a surrounding rock of the roadway.
4. The three-level prevention and control method for roadway rock burst according to claim 3 , further comprising: providing an anti-impact energy-absorbing material on a top beam of the protective support.
5. The three-level prevention and control method for roadway rock burst according to claim 3 , further comprising: arranging a hinged triangular anti-impact device on a top beam of the protective support, and on a bottom beam of the protective support, respectively.
6. The three-level prevention and control method for roadway rock burst according to claim 3 , wherein the protective support is a frame structure formed of splayed columns.