ROBIT -  Pipe Roofing System / Umbrella System is a support system used in loose ground conditions in conventional and mechanized tunneling. It is used to enhance

ground properties to stabilize and reduce risk in tunnel works. It is a method of supporting tunnel by driving pipes ahead of excavation. It is also used in developing the portal sections

and for the re-excavation of collapsed sections in underground works.

Fields of Application

  • Weak Ground Structure

  • Portal Sections

  • Frequently Changing Ground Conditions

  • Re-Excavation of Collapsed Tunnels

  • Urban Tunnelling

The installation of the Pipe Roof System is simple and quick and has the following effects.

  • Reducing the ground loss by creating a boundary of stiff material between the soil and tunnel crore.​

  • Stabilizing the ground in the area of newly excavated and get unsupported excavation round.

  • Distributing loads acting upon the tunnel roof above the freshly excavated round into the in-site ground ahead of the face and the lined tunnel behind the face. Confinement of

  • the tunnel excavation area ahead of the tunnel face.

  • Enhancing tunnel face stability by reducing loads acting upon the tunnel face.

  • Reducing surface settlement.

Pipe Roofing Components

  • Starter Pipe: First Pipe Welded with Ring Bit on one end & female threading on other end, which can be perforated / non- perforated as per the design requirement.

  • Extension Pipe: Male - Female threaded pipe for extension, which can be perforated / nonperforated as per the design requirement.

  • Pilot Bit

  • Drill Rods

  • Grout Plugs / Injection Cap

Threads: Pipe have a trapezoidal thread with double start.

Sizes for Pipe Roofing System: 76.1, 88.9, 101.6, 114.3, 139.7, 159, 168.3   

  • MIPL