Design of long life concrete structures using high performance reinforcing steels

The need to upgrade the large number of aging reinforced concrete (RC) structures that are exposed to aggressive environments, such as de-icing salts in cold regions and sea water requires the development of innovative solutions that will lead to the construction of long life RC structures with low life cycle costs. In this paper, the impacts of using high performance reinforcing steels (HPS), such as 316 LN, 304 and 2205 duplex stainless steels and ASTM - 1035 (or chromium) steel on the service life and structural behaviour of RC structures are investigated. In terms of resistance to chloride attack, 316 LN stainless steel provided the highest value, followed by 2205 duplex steel, chromium steel and then carbon steel. In terms of yield and ultimate strengths, chromium steel exhibited the highest values followed by 316 LN and 22065 duplex steels then carbon steel. In terms of ductility, the RC beams reinforced with 316 LN steel exhibited the highest capacity to deform before fracture, followed by duplex 2205 steel, carbon steel, and then chromium steel. In terms of flexural design of RC beams reinforced with HPS, the same flexural capacity is achieved by using much lower areas of reinforcement for chromium steel, followed by stainless steel and then carbon steel. This suggests that greater savings in material, labour, and maintenance costs are possible when using chromium steel and stainless steel as a reinforcement for RC structures built in aggressive environments, such as highway bridge decks, parking structures, marine and offshore structures.
3rd Congress of the International Federation for Structural Concrete (FIB) and PCI Convention: 29 May 2010, Washington, D.C.