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This paper addresses the lifecycle cost assessment of a steel girder bridge considering the material costs and maintenance activities along the bridge's lifecycle. A reference highway bridge case study is chosen. It was initially designed using carbon steel S355. Two more steel grades are included in the comparison: high strength carbon steel S460 and duplex stainless steel EN 1.4162. For each design option, fatigue appears to be the driving design criterion for the following critical welded details: transversal stiffeners, cope holes and full penetration butt welds in the flanges. In addition to ultimate limit state verifications, specific attention is therefore given to fatigue through the use of different verification methods: the wellknown nominal stress method and the hot spot stress method. It is concluded that the net present value of the lifecycle cost of the stainless steel option is attractive compared to painted the carbon steel options.

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Today, the industrial and scientific community is devoting increasing attention to the effect of hot dip galvanizing on the fatigue strength of structural steel details. In structures such as bridges, hot dip galvanized (HDG) steel is quite often used. Along their lifetime, such structures are repeatedly submitted to stresses of varying amplitudes, leading to fatigue usually being the design criterion. In Germany, recent experimental work on a range of HDG details was carried out, which led to the publication of a guideline recognized as relatively conservative towards HDG components in steel bridge constructions. While, also quite recently, in Norway, recent studies on the behaviour of bolted HDG joints submitted to fatigue concluded that quite similar behaviour compared to uncoated steel equivalents can be expected. The present paper re-investigates, in a uniform and transparent way, the available data for similar uncoated and HDG details. In total, the data for 8 details are presented and discussed. One tries to respond to the question if hot dip galvanizing has such a detrimental effect that, the rules of current version of EN 1993-1-9 should be amended. Finally, the authors give guidance on how the current design rules concerning HDG details should be amended. These guidelines take into account the most recent draft revision of EN 1993-1-9, under preparation by the CEN/TC 250/SC 3 technical group responsible by Eurocode 3.