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Steel-concrete composite floors are commonly used in construction due to their favourable weightto-depth ratio and erection time. Typically, concrete is poured onto a galvanised steel deck acting as formwork. However in case of floors exposed to corrosive environments, stainless steel is likely to be chosen over galvanised steel. Besides its better corrosion resistance, stainless steel also offers desirable aesthetic appearance and good mechanical properties. Composite slabs can fail in bending, vertical shear or longitudinal shear. The latter failure mode is the most common, and its prediction depends on values obtained through full-scale tests. However, for stainless steel decks, no specific treatment exists in current design standards. This paper investigates the longitudinal shear resistance of stainless steel composite slabs through an experimental study. One short and three long span slabs, made using a Cofraplus 60 ferritic EN1.4003 stainless steel corrugated deck, are tested in accordance with Eurocode 4, annex B.3 [1]. The Partial Shear Connection (PSC) method is used to assess the longitudinal shear resistance. The experimental results together with the results provided in [2] are used to draw conclusions on the applicability of ferritic stainless steel decks in composite floors. Stainless steel in composite slabsStainless steel is an alloy with at least 10.5% of chromium and maximum 1.2% of carbon content in mass [7]. Chromium, together with other alloying elements, leads to the development of a thin, passive film when exposed to oxygen, which provides corrosion resistance and which self-repairs when damaged. This means that stainless steel slabs, in comparison to traditional carbon steel slabs, do not need any kind of coating or maintenance. Ferritic stainless steels contain little or no nickel, and hence are cheaper and more price-stable than the other stainless steel families. Furthermore their corrosion resistance is lower, though still significantly superior to that of carbon steel. Besides stainless steel decks have good fire resistance. According to [2], ferritic stainless steel decks retain more of their initial strength than galvanised steel when subjected to high temperature. Corrosion resistance combined with fire resistance makes ferritic stainless steel an economic alternative for composite decks in many applications, such as car parks. Longitudinal shear resistance of composite slabsSince no pure analytical models of the longitudinal shear resistance have yet been developed, both calculation methods for the design resistance available in Eurocode 4 [1], the m-k method and the Partial Shear Connection (PSC) method, rely on full-scale tests.

Steel-concrete composite floors are commonly used in construction due to their favourable weightto-depth ratio and erection time. Typically, concrete is poured onto a galvanised steel deck acting as formwork. However in case of floors exposed to corrosive environments, stainless steel is likely to be chosen over galvanised steel. Besides its better corrosion resistance, stainless steel also offers desirable aesthetic appearance and good mechanical properties. Composite slabs can fail in bending, vertical shear or longitudinal shear. The latter failure mode is the most common, and its prediction depends on values obtained through full-scale tests. However, for stainless steel decks, no specific treatment exists in current design standards. This paper investigates the longitudinal shear resistance of stainless steel composite slabs through an experimental study. One short and three long span slabs, made using a Cofraplus 60 ferritic EN1.4003 stainless steel corrugated deck, are tested in accordance with Eurocode 4, annex B.3 [1]. The Partial Shear Connection (PSC) method is used to assess the longitudinal shear resistance. The experimental results, together with the results provided in Task 3.3 of the "Structural Applications of Ferritic Stainless Steels (SAFSS, RFSR-CT-2010-00026)" project [2], are used to draw conclusions on the applicability of ferritic stainless steel decks in composite floors.

This paper studies the buckling behaviour and design of welded I-section stainless steel columns.Experimental and numerical structural performance data together with the design methods for stainless steel welded I-section columns available in the literature have been collated and reviewed. A numerical modelling programme including validation and parametric studies has been carried out to supplement the literature experimental and numerical data for the assessment of the existing codified and literature proposed flexural buckling design formulations for stainless steel welded I-section columns. Columns of austenitic, duplex and ferritic stainless steel grades undergoing major axis and minor axis flexural buckling have been investigated. From comparisons with the EN 1993-1-4 (EC3) flexural buckling capacity predictions, it was found that (1) for the austenitic welded I-section columns, the EC3 buckling curve (α = 0.76 and λ ̅ 0 = 0.2) is suitable for both axes, (2) for the duplex and ferritic grades, the EC3 buckling curve (α = 0.76 and λ ̅ 0 = 0.2) is conservative, and a higher buckling curve with (i) α = 0.49 and λ ̅ 0 = 0.2 for both axes or (ii) α = 0.49 and λ ̅ 0 = 0.2 for minor axis and α = 0.34 and λ ̅ 0 = 0.2 for major axis may be adopted. In addition, comparisons with the recently proposed Continuous Strength Method showed marginally improved strength predictions but with slightly higher scatter.