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Revisions have been made to the Australian Bridge Code to incorporate modern design principles and best practice standards. The changes are good news for Australia’s 50,000 bridges.

A recent update to the 2017 Australian Bridge Code will help provide a consistent, harmonised and cost-effective approach to the design and operation of bridges in Australia, according to Standards Australia.

In collaboration with Austroads, Standards Australia has revised all seven parts of the 2004 Bridge Code, also known by its Australian Standards series number AS/(NZS) 5100: Bridge design. The 2017 revision also incorporates two new parts covering the rehabilitation and strengthening of existing bridges, as well as timber bridges.

The updated Bridge Code addresses areas like climate change, sustainability, safety-in-design and new technology and new construction materials. The 2004 release of the series was largely concerned with steel or concrete construction, so the recent revision has been extended to include composite (steel-concrete) construction, engineered timber and rehabilitation/strengthening of bridges.

Professor Wije Ariyaratne, Chair of the Technical Committee BD-090, Bridge Code, responsible for the 2017 revisions to AS/(NZS) 5100, said the application of the Bridge Code will result in sustainable and value-for-money designs and technical management of bridges in Australia and New Zealand.

He explained the Bridge Code has been tailored to account for Australia’s exacting and changing design load requirements, as well as evolving contract delivery methods.

“Australia is unique: a continent, an island and a country with an enormous land mass where most freight is transported by road over large distances. Our design and freight vehicle loads are the highest in the world,” he said.

Dr Bronwyn Evans, CEO of Standards Australia, emphasised the importance of the Bridge Code for all those involved in bridge design, build and operation.

“The Committee significantly expanded the scope and identified new parts necessary to comprehensively address modern bridge design and place Australia in a position of leadership,” said Dr Evans.

“This much-anticipated revision has updated technical requirements and references making it a relevant and critical document for industry.”

 

Steel and composite bridges

Part 6 of the nine-part AS/NZS 5100 series is unique as it is the only one to represent a harmonised standard between Australia and New Zealand (the other eight parts are Australian Standards only).

The differences between the revised version of AS/NZS 5100.6 Bridge design: Steel and composite construction and the 2004 version on which it is based relate to new fatigue provisions and new welding provisions. Specifically, the major changes to Part 6 are as follows:

  • Introduction of concrete compressive strengths up to 100 MPa together with quenched and tempered steels with a yield strength of up to 690 MPa
  • Updated design rules to address: a) resistance of headed stud connectors b) resistance and buckling strengths of composite columns c) fatigue verification
  • Provides reliability differentiation during fabrication and erection with due reference to the new workmanship Standard AS/NZS 5131 Structural steelwork – Fabrication and erection.

Arun Syam, Business Development Manager at Liberty OneSteel, said: “The revisions to Part 6 will serve to guide designers, asset owners, authorities and fabricators in the use of updated construction materials and methodologies. They will also assist engineers in verifying potential structural and serviceability failures by using up-to-date design methods and fabrication specifications.”

Of the wider revisions made to the series, Syam said that the new Bridge Code will play an important role in standardising bridge design, fabrication, erection and operation.

He added that customers using Liberty OneSteel products will gain further confidence in their use of compliant structural steels for strategic and critical applications.