1. Strong applicability
Self drilling rock bolt has strong applicability, especially in soft rock. Drill pipe can be combined with bolt, self drilling rock bolt can be drilled into the rock and soil directly, the hollow of bolt can be used as grouting channel, grouting from inside to outside. There is no need to make holes and without casing wall in backfilling area, weathered rock, broken rock, sand and clay layer, as well as the pebble bed, ect.
2. Boost grouting method
Grouting method is to return the pulp from hole bottom and a step-grouting. Due to the occluding plug design of self drilling rock bolt, pressure grouting can be realized. Grouting pressure can be controlled according to the design value, and can boost to the design value at a time. The pressure maintenance time is not less than 10min while spilling slurry from orifice, can achieve full penetration of the slurry rapidly along the rock fissures, and grout diffusion radius is big, surrounding rock cemented into a whole after consolidation to achieve the purpose of permanent rock anchors.
3. Overlength bolt anchoring for confined spaces
Continuous thread of the self drilling rock bolt can be cut and connected willfully, achieving the purpose of anchoring dangerous rocks in the narrow space. Meanwhile, continuous thread of the self drilling rock bolt has stronger bonding resistance than smooth steel pipe, 2-3 times higher than ordinary mortar anchor rod.