Evaluation of the effect of connection fracture and configuration of fracturing connections on seismic performance of steel moment frames

Document Type : Research Article


Assistant Professor, Faculty of Civil Engineering, Imam Khomeini International University


Provision of ductility has always been of concern in seismic design of structures. However, large
variability in connection performance is observed during the recent earthquakes, due to brittle fracture of
steel moment frame connections. In this study, distribution of early fracturing pre-Northridge connections
is optimized by genetic algorithm tool to quantify the sensitivity of seismic response of the structures
to spatial variation of early fracturing connections for two hazard levels. Also, a non-degrading ductile
connection is modeled to compare the seismic performance of the structures. Probability assessment
is carried out by implementation of incremental dynamic analysis to find the reliability of structures
under this condition. Results show that configuration of fracturing connections in beams, in contrast to
columns, can significantly affect the collapse capacity of structures.


Main Subjects

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