تاثير ارتفاع بر ضريب رفتار قابهاي با مهاربند زانويي

Moment resisting frame system and concentric braced frame system are two systems that are used widely in earthquake resistant buildings. But none of them can respond stiffness and ductility demands simultaneously caused by severe earthquakes. In this study, seismic behavior of knee braced frame system (as a suggested solution to remove this problem), has been investigated. In this system at least one end of braced element, instead of connection to intersection point of beam-column, is connected to inclined knee element that is located between beam and column. Braced element supplies the stiffness of system, whiles the ductility under severe lateral loads, and is secured by flexural yielding of knee element. The knee element acts as a ductile fuse and prevents buckling of braced element. In this research, the behavior of knee braced system with different sizes under El Centro earthquake by non-linear Drain-2DX software was examined. This study is done for frames with 5, 10, 15 and 20 stories. Finally, the effect of building height on the behavior factor is investigated.