Soil nailing is a method of soil reinforcement for the stability of the natural soil. Self drilling anchor bolt bears tensile strength as a soil nail, and also bear the bending load and shearing load. Soil nailing is very economical, which can improve the self stability of soil. Self drilling anchor bolt provides frictional force, shearing resistance and tensile force in loose stratum in soil nailing.
The soil nailing structure usually consists of self drilling anchor bar, coupler, nut, plate, centralizer and drill bit. The structure has the following features:
1. The bending moment, shearing force and adhesive property of self drilling anchor bar are obviously better than that of the solid bar;
2. The coupler has an stop end, which makes the anchor bar end-to-end so as to reduce the energy loss and effectively ensure the high efficiency of drilling;
3. Both the hex nut and domed nut are available, playing the role in fixing the plate;
4. The centralizer is fixed at the front end of the coupler, at least one piece per 3 meter, which can ensure self drilling anchor bolt is in the middle of the borehole, and the thickness of the cement slurry layer around self drilling anchor bolt is not less than 20mm;
5. Both the flat plate and domed plate are available. In general, R25, R32, R38 self drilling anchor bars match with domed plates, while R51, R63 and T-thread self drilling anchor bars match with flat plates.
6. The disposable bit can drill into the hole directly. There is no need to pull it out. It’s safe and efficient.