Recently IBODRILL employees attended a seminar on tunnelling and underground support. Tunnel project designers and Geo-drilling products manufacturers shared ideas on tunneling method and new technology.
Here is a brief review of how IBO self-drilling anchor bolts are applied in NATM tunneling and other ground reinforcement works.
Construction method of mountain tunnel
NATM: new Austrian tunnelling method
The basic principle of NATM: Less disturbance, Early support, Ground measurement and Tight closure.
Anchor Bolting: A kind of reinforced bar which is inserted into rock/soil body, for active reinforcement of surrounding rock.
Anchoring method of anchor bolt:
Anchor rod full fills binding material.
Tension anchor rod for anchorage with tension requirements.
Anchor rod by anchoring force between bolt body and hole wall.
The anchor rod itself has the integrated function of drilling the hole, grouting, and anchoring. Sometimes it is called SDA or IBO.
Consistent with the service life of the main project, the project can maintain stable performance and quality standards during the effective operation period, or have the repair and replacement conditions, the role of sustainable development of the anchor
The temporary anchor bolt can not reach the standard of the service life of the main project, only requires the anchor rod in the construction or the specific stage of the project, the normal working conditions of the project generally do not consider its role.
Below is a document about NATM technology and IBO self-drilling anchor application.