Fire after Earthquake Analysis of Steel Moment Resisting Frames

Fire following earthquake can cause substantially loss of life and property, added to the destruction already caused by the earthquake, and represents an important threat in seismic regions. On the other hand, even when no fire develops immediately after an earthquake, the possibility of later fires affecting the structure must be adequately taken into account, since the earthquake induced damages make the structure more vulnerable to fire effects than the undamaged one. The paper presents the evaluation of the fire resistance time for some unprotected steel moment resisting frames, in the hypothesis that they are already damaged by the earthquake, using advanced methods for earthquake and subsequent fire analysis, and using both standard and natural fire scenarios. Moderate and severe seismic actions are used for designing the steel structures. The influence of the damage level induced by the earthquake on the fire resistance is emphasized.