IDA & CLOUD METHOD FOR FRAGILITY ASSESSMENT OF BARE & INFILLED STEEL FRAME STRUCTURES

In this study, the seismic performance of two- and four- storey steel framed structures has been assessed and compared in terms of capacity and fragility. Full scale three-dimensional models of the selected structures have been simulated once as bare steel frame and once while considering the effect of masonry infilled panels, to have the most realistic representation. Furthermore, the selected structures have been designed following two methods of only gravity loading and considering additional seismic excitation. The seismic behaviour has been evaluated through Incremental Dynamic Analysis (IDA) and the Cloud method (NLTHA). A comparison of resultant structural behaviour and fragility functions for both bare and infilled cases indicates that the structural effect of masonry infill panels should not be neglected, as they have a significant influence on the lateral stiffness, strength and ductility of the entire structural system and ignoring it would be hazardous.