VULNERABILITY ASSE SSMENT OF A 3-STORYSTEEL BR ACED FRAME WITH KHORJINICONNECTIONS AND INFILLS IN TEHRAN

Connection failure of extr emely large number of steel buildings with semi-rigid "Khorjini"connections has been reported in past major earthquakes in Iran (i.e. Bam-2003 and Manjil-1990).In the present paper,atypical 3-story steel braced-frame ضuilding with “4horنini” connec tions with infill wall is selected and the incremental dynamic analysis (IDA) is performed to investigate its s eismic performance.The probability of exceeding desired performance limits on future probable earthquakes in Tehran are estimated for Tehran.In order to develop suc h fragility curves, 44 records as offered by ATC -63 are adjusted for the study area and used to perform nonlinear analyses. IDA-generated fragility curves are presented forImmediate Occupancy (IO), Life Safety (LS) and Collapse Prevention (CP) limit states performance. The results showed 56% probability of exceeding the CP performance level for earthqua kes with a return period of 2475 years. For return period of 4 75 years, this valuewas16%.