Investigation of Performance Based Plastic Design Method of Steel Moment Frames with RBS Connections

Earthquakes in recent years showed that design of structures using force method is not a reliable method for design of structures against earthquake. Performance Based plastic Design is developed as a modern way in seismic design of structures in order to refine the seismic performance of stable buildings faced to earthquake. In this way use the balance of internal and external work to calculate the base shear. Also, this method provides a new distribution of internal force that nonlinear effect of higher mods can be considered in the design of structures. Select the target displacement and remove the undesirable mechanisms at the beginning of the design process is another advantage of this method compared to the force method. This paper assesses the force and performance based plastic design method for Special Moment Resisting Frames whit RBS connection. By this point, four buildings with 4, 8, 12, 20 stories of Special Moment Resisting Frames Based on Iran Building Regulations, and for the second time attempted to apply plastic design based on Performance based Design method. Performance based Design Method was applied and Pushover Analysis on The Original Building carried out. Performance and yielding mechanism of the buildings showed that both types of limit states satisfied the Life Safety level, although under severe earthquake record satisfied Immediate Serviceability level. Performance Based Design under stronger excitations reached for target point mechanism, but in the Force Based Design Method was observed that Performance Based Design is as beneficial as Force Based Design Method.