1. Strong applicability.
Self drilling rock bolt has strong applicability, especially in weak surrounding rock, it combines drilling and anchoring together. Self drilling rock bolt can be directly drilled into rock and soil. Its hollow bar can also be regarded as grouting gallery from inside to outside. It doesn’t need pore-forming and casing pipe to protect wall at back filled region, decomposed rock, broken rock, sand layer, clay layer, pebble bed and other weak surrounding rock.
2. Pressure grouting method.
Grouting is from bottom, which can realize pressure grouting. It should be controlled according to design value. Pressure maintenance should not be less than 10 min when grouting at orifices. Pressure grouting can rapidly make slurry fully permeate into cracks of rock and soil. After slurry diffusion and concretion into integrity, which can reach at purpose of permanent anchoring surrounding rocks.
3. Simple and fast for construction.
Continuous international screw thread and coupler make the process, installation and lengthening of self drilling rock bolt simple and fast for operation. After drilling to designed depth, it can instantly realize borehole cleaning, pressure grouting and self drilling rock bolt doesn’t need to be pulled out. Compared with common hollow rock bolt and common mortar rock bolt, its construction process is simple and benefit is obvious.
4. Lengthened to reinforce in narrow space.
Continuous screw thread can make self drilling rock bar be cut and connected arbitrarily. In narrow space, it can realize reinforcement of dangerous rock. At the same time, continuous screw thread of self drilling rock bolt has stronger bonding resistance than smooth steel tube, about 2-3 times than common mortar rock bolt.