In Eurocode 3: Design of steel structures –Part 1-2: General rules – Structural fire design, the temperatures in the steel section are assumed uniform and the thermal properties are assumed constant. This leads to conservative and possibly uneconomic designs. In particular, steel sections embedded in or in direct contact with concrete are not considered appropriately - only the reduction of the exposed area is taken into account. In addition, the shadow effect is rarely considered in structures with both concrete and asteel elements such as composite floors. It has been mainly used for stand-alone columns with I-cross section. In this paper, the temperature distributions in a steel beam with or without considering the shadow effect are calculated using the program TASEF. The resulting temperatures are then used to determine the fire duration under loading using a finite difference based computer program COMPSEF for the mechanical response. The differences in failure times reflect the savings that can be made using such ‘advanced calculation models’ permitted in Eurocode 3, when compared with the prescriptive methods included in the code.
20th International Conference on Computer Methods in Mechanics: Cmm 2013, 2013
structural fire engineering; heat transfer; shadow effect; finite difference method
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20th International Conference on Computer Methods in Mechanics, 2013