Self-Drilling Anchor systems are used when the bond behavior is critical for the level of safety required on tunneling contraction. Self-drilling Anchors are successfully used for reinforcement ahead of the tunnel face in terms of spiles or spile umbrella support, additional reinforcement, and supplementary anchor works.

The advantages of the Self-drilling system are:

       • Variable applications.

       • Especially advantageous in rock/soils with low cohesion.

       • Simple to install in unstable boreholes.

       • No stalling when drilling across clefts.

       • Drilling and installation in one cooperation.

       • Grouting assured over full depth of the borehole.

       • No need to extract drill strings.

The main applications of Self Drilling Anchor Systems in Tunnel Construction

Self-drilling spiles • For stabilization ahead of working face • For safeguarding operations at the working face	Rock bolts • Anchoring system can accommodate rock pressure • Local stabilization of blocks and fault zones • Follow-up rock stabilization	Tunnel face anchors • Stabilization of working face in squeezing rock masses. • Stabilization of working face when using pipe umbrellas	Tunnel floor reinforcement • For strengthening the base of the tunnel arch