Hollow Bar Friction Anchoring Systems

Injection Anchors

Injection Anchors are ideally suitable for post-tensioned tie-back anchors, to secure sheet pile walls, soldier pile and timber-lagging walls and bored pile walls.

The grouted anchors transfer the tensile forces from the steel rod to the grout body to the surface friction into the soil.

All grouted anchors have a free anchor length. They are post-tensioned to approximately 80% of their designed working load.

The Injection anchor is a single rod anchor which consists of an anchor tube as a load carrying cross section which can be coupled. The Injection anchor is a tubular anchor.

The coarse, rebar-like thread conforms to DIN 488 and meets other international rebar thread standards. This continuous thread allows it to be cut on site, and it can be extended by couplers. Threaded drill bits are adopted for various types of soil, and can be screwed on. Spherical collar nuts to secure the couplers are not required due to the slow pitch of the thread. At the same cross section, from the static point of view, the anchor tube is superior to a full rod with respect to bending, horizontal loads and surface friction.

The advantages of Injection Anchors are:

  • Drastically increased productivity by eliminating installation and removal of casings
  • Smaller drill rigs and equipment, working in cramped quarters
  • Anchor tubes can be lifted by men
  • Same installation principles for all different soils without the need for an extensive soil investigation
  • Continuous thread allows extension by couplers
  • High class constructional steel meet with rugged requirements of the job sites
  • Simple post-tensioning of anchors
  • High shear connection between anchor thread, grout body and soil
  • The free length can simply be extracted