- Publication no: ABC2017-123-17
- Published: 26 April 2017
Weathering steel is a high strength low alloy steel that, in a suitable environment, may be left unpainted due to the formation of an adherent protective rust “patina”. This patina significantly retards the corrosion rate, which is 5 to 10 times less than that of uncoated mild steel. Examples of weathering steel exhibiting excellent performance, are found in North American, Europe, Japan and New Zealand since its first use in the US over 50 years ago. These include examples which clearly show that a well-designed and detailed weathering steel bridge, in an appropriate environment, can provide an attractive, very low maintenance, and economic solution.
Working with NZ Heavy Engineering Research Association (HERA) and Opus International Consultants, BlueScope Australia has prepared an industry design guide that outlines the correct use of AS/NZS 3678 weathering steel (WR350 and WR350L0) in Australian bridges. This document covers design, fabrication, construction, inspection, maintenance and even rehabilitation of weathering steel bridges. These topics are summarised in this paper, highlighting the important aspects that designers need to consider when specifying weathering steel for bridges.