Australian Standards: Ensuring welded structures and the general public are safe

Weld Australia has taken responsibility for maintaining Australian Standards and managing the adoption of International Standards related to welding.

The purpose of both Australian and International Standards is to ensure that welded structures are safe. Standards have been developed, reviewed and revised over many years by volunteer engineers and tradesmen who are enormously experienced in the design and construction of welded structures. In this way, the accuracy and validity of technical data and specifications contained within Standards is indisputable.

If applied properly, Standards ensure that fabricated structures meet all design criteria, are fit for purpose, and remain structurally sound for the entire lifecycle of the asset. The application of Standards to a process such as welding is particularly important— it is impossible to undertake complete verification of a welded joint without destroying it. Unfortunately, inspection after completion does not guarantee weld serviceability. As such, quality must be built into the welding process, right from the very beginning.

Welding must be done correctly the first time. A weld cannot be adjusted once it is complete. The only course of action is to scrap the weld entirely, and start again. As such, the welding processes set out in Australian and International Standards are crucial—they must be followed exactly.

If Australian and International Standards are not followed exactly, then there is a significant chance that a structure will fail.

Just such a failure occurred recently in Holland. High winds caused part of Dutch club AZ Alkmaar’s stadium to collapse. Dramatic pictures emerged of the damage to the 17,000-capacity stadium in Alkmaar, which was built 13 years ago. Luckily, the stadium was empty at the time. In this case, the European Welding Standards weren’t followed, and the roof failed.

I would like to be able to say that this will never happen in Australia. But, I am aware of many structures in Australia have been built using welds that fail to comply with the relevant Standards.

What is of perhaps most concern is that when such failures are pointed out to consulting structural engineers, they argue that—despite the fact that welding Standards are not adhered to—the structure is still safe. Engineers often make this judgement under pressure, with weld faults usually not discovered until a structure is almost complete.

For example, Weld Australia was recently retained as the Engineer of Record by an Australian state government for a pedestrian bridge fabricated overseas. Throughout the construction phase, Weld Australia was unable to access the project, despite repeated attempts to confirm that the project met Australian standards. Therefore, Weld Australia could not certify that weld procedures were in place, that welders were qualified, and that supervision and inspection practices met the standards.

As the bridge was comprised of tubular structural steel with complex nodes, it was critical that full penetration occurred on all joints. Given the circumstances, Weld Australia was not confident that full penetration had been achieved. When the bridge components were ready to be delivered, the state government asked us to certify the welding, which we refused to do.

At this point, the engineering company produced a highly experienced expert arguement why we should certify the bridge as safe. The expert was unable to demonstrate to our satisfaction that the structure met all the requirements of the design and the Standards. Again, we refused to certify the welding. To their great credit, the state government concerned scrapped the fabricated steel and had the pedestrian bridge re-fabricated in Australia.

Unfortunately, not all projects result in such a successful outcome.

Weld Australia was recently informed by a whistle-blower of a structure in Australia that has been fabricated without compliance to Australian Standards. When we inspected the structure, we discovered that it was totally non-compliant, and deemed it to be unsafe.

Again, the consulting engineers argued that Australian Standards need not apply. However, in this case, the state government involved accepted the argument of the consulting engineers and continued with the fabrication and erection of the structure. In our view, the non-compliant welds in this structure are placing the public in harm’s way.

Australian and International Welding Standards are quite clear. Either Standards are complied with and a structure is safe, or they are not complied with and a structure is dangerous. As such, it is of significant concern that engineers are trying to second-guess the Standards.

Engineers are making assumptions, and then relying on these assumptions to certify a structure, and the welds within, as safe after the fact. This simply does not work. Welding must be performed correctly the first time to ensure that stadium roofs, pedestrian bridges, and major structures do not collapse.

Standards exist for a reason; to ensure public safety. When it comes to welding, we cannot simply wave a magic wand and make a weld safe after the fact.

Article by Geoff Crittenden, CEO, Weld Australia