The slowing of the heating of a steel profile linked to hot-dip galvanizing has been highlighted by several research studies, including not only standard or natural fire tests, but also an analytical approach. This work led to a proposal for an amendment to Part 1-2 of Eurocodes 3 and 4 regarding the fire design of steel (Eurocode 3) and composite steel and concrete (Eurocode 4] structural members. This amendment recommends a 50% reduction of the surface emissivity of a carbon steel profile as long as the applied zinc coating is present, followed by a «retum to normal» of the steel's fire behaviour once the zinc layer has melted. The adoption of this amendment will make it possible to consider hot-dip galvanizing as a kind of passive protection of a steel structural member, in particular for fire resistance requirements of less than 60 minutes.
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