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Evaluation of Behaviour Factor of Concrete Precast Structures Braced by Steel Elements

Nowadays, concrete precast structures has found a particular situation in building industry. One of the resisting systems against seismic loading in these buildings is steel bracing with direct connections predicated advance. The force reduction factor is a coefficient that contains inelastic behaviour and shows hidden resistance and ductility of structures in the inelastic zone. With attention of behaviour factor in structural seismic design seems the determination of this factor is necessary. The aim of this research is to determine of force reduction factor for the precast concrete frames braced by steel elements. For this purpose, the precast concrete frames with three bays have been used. The bays width is equal to 6 meters and the story height is equal to 3 meters. Some parameters like the number of stories (4, 8, 12 stories), the rigidity percentage of frame precast connection of beam to column (0, 25, 50, 75, and 100 %), the number of braced bays (1 or 2 bays), the position of braced bays, the effective stiffness coefficient for the reinforced concrete members, the lateral load pattern, effects of eccentric bracing, and evaluation of 3-dimensional frames on the reduction factor have been investigated (the rigidity percentage of zero stands for hinge connection, and rigidity percentage of 100% stands for rigid connections and rigidity percentages of 25, 50, and 75% stands for semi rigid connections). To receive this goal, the static pushover analyses have been used.