About Signfix aluminium frangible poles
In 1997 the Roads and Traffic Authority of NSW carried out a series of crash tests at the RTA’s Crash-Lab in Sydney.
The test results successfully proved that pole sizes 50, 65, 80, 90 & 100mm NB fell within the frangibility guidelines of the NCHRP-350 Standard for open road conditions.
Subsequently the Signfix frangible pole system has been approved and used by Transit New Zealand, VicRoads, Transport SA, Main Roads WA and Queensland’s Department of Transport and Main Roads.
The patented system works in conjunction with a purpose made ground sleeve designed to be a snug fit between pole and socket.
Depending on the pole diameter sleeves can be supplied from 300mm to 1m lengths. Sleeves are set in concrete foundations designed to meet local engineering requirements.
The sleeve top acts as the shear point and combined with the molecular structure of the alloy will, under sudden impact, bend the pole at the point of impact and will ultimately shear and breakaway at the socket top.
The pole flutes are designed to further assist in the breakaway process by reducing the external surface area of the pole.
Both pole and sleeve are manufactured from high strength marine grade alloy with a typical yield strength of 240 MPa. This alloy has good age hardening qualities and will continue to strengthen over time.
For further technical information consult the crash test report, structural information and installation guide available from Signfix
Features and Benefits
- Poles are light and easy to handle and convenient to transport.
- Pole sizes are standard allowing all available bracket types and brands to fit.
- Signfix Aluminium frangible poles are similar in strength to steel equivalents.
- Manufactured from marine grade alloy Signfix fluted poles will remain maintenance free for whole of life.
- Poles are simple to install with no specialist equipment required.
- When using ground sleeves in conjunction with larger poles, props are not required during the foundation hardening process.
- Breakaway restraining device available.
- Frangibility is multi directional.
- In the event of damage frangible poles can be easily removed and replaced without interfering with existing foundations.
- Stainless Steel Transition Shoe is supplied to prevent wear and eliminate any electrolysis action between the locking bolts and pole.
- Correctly installed the Signfix fluted pole and socket system is fully frangible and meets the requirements of NCHRP-350.