Providing safer access for maintenance crews

Opus provided structural design and construction services for steel-framed walkways inside the Sydney Harbour Bridge pylons.

The walkways were needed to provide safer access for maintenance crews to key parts of the bridge superstructure. The bridge's heritage status presented a number of design and construction challenges.

The walkways had to be lightweight to avoid overloading existing bridge members, and could only be supported by the existing structure in specific locations. Furthermore, drilling and welding of the bridge superstructure was not permitted.

Opus designed a highly efficient truss system to minimise dead weight loading, and the walkways were suspended from the roadway support structure using a system of removable clamps.

Close attention to detail was required to accommodate the existing structure and ensure the design could be constructed in a safe and straightforward manner. The walkways were prefabricated in segments whose sizes were governed by both dimensional and weight constraints so that they could be installed using a rigging system rather than a typical construction crane.