PAR1 Bolt

PAR1 Bolt


The PAR1 Bolting system is an end-anchored yielding bolt that is grouted post-installation and can be supplied with attachment points for meshing and lacing. The end anchor provides immediate support upon installation and two pairs of double paddles act as additional anchors once the bolt is grouted.

The PAR1 Bolt can be supplied with 18 mm or 20 mm bar depending on requirements. The unit has an elongation of 23% in static conditions and 15% under dynamic loading. The unit is provided with a collapsible load indicator to confirm correct tensioning of the unit when installed. The end of the bolt protruding from the hole has a threaded section over which a washer is placed and held in place by a nut, which is also used for pre-tensioning of the unit. A specially designed seal ensures easy grouting of the installed PAR1 with minimal spillage of grout during pumping. An optional non-return valve can be incorporated in the grout seal to prevent any leakage of grout once the pumping system is disconnected.

Benefits of the PAR1 Bolt

  • High yield ability
  • High energy absorption
  • Fully mechanised or manual installation and grouting
  • Immediate support
  • Pre-tensionable with load indicator
  • Easy grouting with no spillage
  • Includes attachment points for meshing and lacing directly onto the bolt

PAR1 performance specifications

Dimensional Specifications Ø18 Ø20
Bar diameter Ø18.3 mm, DIN 405 RD 20 Ø20.3 mm, DIN 405 RD 22
Length of bolt 1.8 m to 3.0 m 1.8 m to 3.0 m
Typical length of thread (adjustable) 300 mm 300 mm
Steel Specifications Ø18 Ø20
Yield strength minimum 500 MPa 500 MPa
Yield load typical 127 kN 157 kN
Ultimate tensile load typical 162 kN 229 kN
Elongation* Ø18 Ø20
Average 26.13% 26.13%
Standard deviation 2.17% 2.17%
Guaranteed static 22% 22%
*Tested as per SANS 6892-1:2010 (Ed. 1.00)


PAR1 Bolt Uncoated

Standard uncated bolt

PAR1 Bolt Zinc Coated

Thermal zinc diffusion coating

PAR1 Dynamic Testing