Hollow drilling rock bolt combines functions of drilling, grouting and anchoring, is an advanced anchoring and support system, which can solve problem of hole collapse and ensure grouting effect under complex geological condition.
At aspects of bending resistance, shearing strength and surface bonding, hollow drilling rock bolt is better than mortar anchor bolt with the same section. Hollow drilling rock bolt can be cut, connected, exerted prestress and released load arbitrarily. Also, it can be used as grouting pipe. Production process is simple and it has quite large application values.
One-off drill bit cancels withdraw of hollow drilling rock bolt from drill hole, it can avoid hole collapse and rework.
Through hollow drilling bar and drill bit with holes, slurry can enter and fill in cracks of stratum, which can ensure rock consolidation and anchoring quality. When pure slurry flows out, grouting can be stopped.
Plate and nut can exert prestressed force to stratum.