Thrie Beam Guardrail

Thrie Beam with C-Posts

Low Deflection. Compliant to AS/NZS 3845.

Thrie-Beam with Standard Blocks is a stronger version of the w-beam guardrail systems. The additional corrugation in the thrie-beam rail element stiffens the system, making it less prone to damage during low- and moderate-speed vehicle impacts. It also allows higher mounting of the rail, which increases its ability to contain vehicles larger than standard passenger cars under some impact conditions

Thrie-Beam with Standard Blocks is compliant to AS/NZS 3845 and is deemed to comply with the requirements of NCHRP Report 350 Test Level 3.


    • The additional corrugation in the rail element stiffens the system.
    • Shields hazards located closed to the edge of the roadway.
    • The post and block design reduces wheel snagging and the consequential effects of vaulting or rollover.
    • Performs well on the outside of curves, even those of relatively small radius, as the concave shape (in plan view) supports the development of tension in the rail.
    • Can be used in verge or median locations.
    • Compliant to AS/NSZ 3845.
    • Hot dip galvanised in accordance with AS/NZS 4680.
    • Standard Post spacing: 2m.
    • Height to top of rail;
      • 805mm (SA & WA).
      • 825mm (Qld & WA).
    • Dynamic deflection at 2.0m post spacing: 0.6m* (2000kg vehicle at 100km/h and 25°).
    • Recommended minimum Length: 30m.**
    • Where a kerb exists at the edge of the road, it is recommended that the barrier be placed within 200mm of the face of the kerb or a distance behind it to ensure that impacting vehicles do not vault over the barrier.**
    • Recommended minimum distance between the rear of the system and the hinge point of the batter: 600mm.**