CROSS Safety Report
Fabrication issues with imported steelwork truss in Australia
This report is over 2 years old
Overview
A reporter raises concerns after a steel truss had significant defects and deflected after erection requiring rectification.
Key Learning Outcomes
For the construction team and steel fabricators:
-
Quality control and competent supervision can help to ensure that steel trusses are fabricated in accordance with the design requirements
-
If steelwork is procured and fabricated overseas it is good practice to inspect the trusses prior to them being shipped
Full Report
Find out more about the Full Report
The Full Report below has been submitted to CROSS and describes the reporter’s experience. The text has been edited for clarity and to ensure anonymity and confidentiality by removing any identifiable details. If you would like to know more about our secure reporting process or submit a report yourself, please visit the reporting to CROSS-UK page.
The truss structure shown in Figures 1 and 2, says the reporter, illustrated significant defects and deflected after erection requiring rectification. The builder undertook repairs on site, including reinforcing the areas where cracking occurred in the junction between cross beams and main truss beams and welding reinforcing tubing alongside sections of the cross beams that had split.
This work was however deemed insufficient to stabilise the structure and as a result another tenderer was engaged to rebuild the truss. In this process the original steelwork was removed and taken to their yard. Several additional defects and instances of non-compliance to the relevant standards were found. Tensile testing showed the steel was 338 MPa yield strength versus a 450 MPa grade to AS/NZS 1163 Gr 450L0 called up in the engineer’s documentation.
There were also other non-compliances. These cover AS/NZS 1554 welding, and the material specification AS/NZS 1163 for the hollow sections.
Submit a report
Your report will make a difference. It will help to create positive change and improve safety.
Our secure and confidential safety reporting system gives professionals the opportunity to share their experiences to help others.
Feedback
As Chair of Standards Australia Committee BD/1 which is responsible for AS 4100 Steel Structures, and AS/NZS 5131 Structural Steelwork – Fabrication and Erection, we are in the process of a major revision to these standards to deal with some of the issues cited.
Basically we are removing fabrication and erection provisions from AS 4100 and including most of them as appropriate in AS/NZS 5131. We are then making direct reference to AS/NZS 5131 from AS 4100. The main intent of this is to make AS/NZS 5131 a secondary reference to AS 4100 within the National Construction Code. This means that AS 4100 can now include reference to the construction specification as the document containing the particular design data and details to be provided as one deliverable from the design process.
The revised standards are expected to go out for public review in May 2019. It is hoped that the revised standards go some way to address some of the issues raised by CROSS-AUS.
Expert Panel Comments
Expert Panels comment on the reports we receive. They use their experience to help you understand what can be learned from the reports. If you would like to know more, please visit the CROSS-UK Expert Panels page.
This is an abbreviated version of a much longer report and describes a structure which had numerous problems. A complex fabrication such as this needs competent input at all stages. This report is primarily about defective workmanship and use of steel having inadequate strength but the comment about deflection after erection is curious.
Deflection is governed by design and the steel’s E value (which is not related to strength) and so perhaps there are aspects that could be related to design. The report demonstrates that steel member capacity is just as much governed by fabrication quality as design and that all projects require adequate documentation and inspection to assure that what the designer thought was being provided was actually provided.
Deflection is governed by design and the steel’s E value (which is not related to strength) and so perhaps there are aspects that could be related to design.
This applies wherever the fabrication is carried out and where standards may be misconstrued. Physical examination of the processes in-situ may be advisable. CROSS has previously warned of inadequate documentation accompanying imported components: Anomalous documentation for proprietary products - February 2013.
CROSS-AUS NOTE: Since this Report was published in 2014, Australian Standard AS5131 – Structural Steel Fabrication & Erection was published in 2016 and CROSS-AUS would like to receive your feedback on any similar fabrication issues or whether practice has improved.