ABSTRACT
Several great historical earthquakes (San Francisco 1906 and 1989, Tokyo 1923, Kobe 1995) testify for the high risk coming from fires developing soon after earthquakes. The obstruction of access roads caused by rubble and collapsed buildings in the streets, the possible difficulties in water supply soon after the earthquake as well as the concomitance of multiple fires are some possible factors contributing to such a risk. Besides, earthquake-induced damages to both passive and active fire protection systems could add the additional factor of the decrease of the building’s fire resistance rating. This paper presents several results of a numerical investigation, aiming at obtaining some quantitative information about the fire resistance ratings of earthquake-damaged multi-story moment-resisting steel frames. Multiple levels of earthquake intensities, hence earthquake-induced damage, are considered by scaling acceleration records to increasing values of the elastic pseudo-acceleration. Moreover, two building structural systems are considered, one characterized by moment-resisting frames only at its perimeter, the other characterized by moment connections in all the bays.
