Stainless Steel for 100 Year+ Design Life

Stainless Steel for 100 Year+ Design Life

Stainless steel has delivered the confidence it will provide the structural performance and meet the 100-year life-cycle of a new marina development on the New South Wales’ South Coast.

The Waterfront, Shell Cove, is a joint residential and mixed-use development between Shellharbour City Council and Frasers Property Australia located 22km south of Wollongong.

Central to the development is its waterfront location and world-class marina that will offer pontoon berthing for approximately 270 vessels, direct access to the Pacific Ocean, charter boat operations, a public boat ramp and a variety of marina facilities and services.

Stainless steel reinforcement has played a significant role in the structural design and construction of the marina, with over 318 tonnes of grade 2304 lean duplex stainless steel reinforcement bar (rebar) supplied by ASSDA Member Valbruna Australia. Ranging in diameters from 8mm to 25mm, stainless steel rebar was used in all pre-cast elements to form the marina sea walls, marina steps and boat ramps and installed by Coastwide Civil.

The original project specification was for alternative materials and products with cathodic protection and sacrificial anodes that struggled to exceed a 50-year life-cycle guarantee. This specification was superseded by a requirement for a 100-year life span, and the use of stainless steel provided the best solution, as well substantial cost savings around constructability and man hours per tonne required.

Stainless steel rebar offers structural longevity in many environments with exceptional corrosion resistance in harsh marine developments. Its specification in this landmark waterfront development meets the expected minimum 100-year life and was also critical to minimising ongoing maintenance costs. This was an important consideration to avoid future maintenance closures due to corrosion issues and to ensure continued public accessibility to the waterfront promenade for all residents and tourists.

In addition, the use of stainless steel rebar significantly reduced the amount of concrete cover required, also minimising costs and resulting in a more lightweight and higher tensile strength structure.

Valbruna Australia’s commitment to stock large volumes of stainless steel rebar on the floor in Australia meant no delays were experienced during the project’s supply term, including meeting the 20% increase in supply quantity during installation. Coordinated supply was critical to the on-time completion of the project, which was further impacted by narrow site delivery windows and limited set down holding areas.

The scheduling, cutting and bending of the stainless steel rebar to tight precast tolerances was completed by Mesh & Bar, and performed at a dedicated stainless steel facility to prevent contamination risks.

All stainless steel welds were completed in a controlled environment, and pickled and passivated by Waeger Constructions.

Construction of the residential and mixed-use infrastructure will continue into next year, with the marina due to take water by the end of 2019. Once completed, Shell Cove will also boast a vibrant town centre and retail precinct, community centre and library, foreshore dining and waterfront tavern, and boutique accommodation.

This article featured in Australian Stainless magazine - Issue 63, Spring 2018.