DYWIDAG Expandable Rock Bolt

Instant stabilization without grouting.

DYWIDAG Expandable Rock Bolt is a non-grout fastening system for quickly stabilizing challenging conditions in rock and soil masses during the excavation of tunnels, mines, and caverns. As they do not depend on grout strength, this solution provides immediate full-length strength, allowing faster and safer excavation.

The DYWIDAG Expandable Rock Bolts are placed in drilled holes and expanded using water from the installation water pump. A combination of friction and mechanical interlocking is achieved throughout the entire bolt length, providing instant support through direct load transfer from ground strata to the bolt.

They are made from special steel tubes that have been folded to create a unique profile that ensures higher shear performance.

  • Immediate ground support, enabling faster and safer excavations

  • Grout-free installation, saving construction time and cost

  • Easily adjusts to deformities if there is any ground movement, reducing the need for re-work

Main standards steel nuances

Asia: Nominal ultimate loads 120 kN, 160 kN, 200 kN and 240 kN​


  • Supply of DYWIDAG Water Pumps

  • Angle compensation at anchor head by using a domed plate