چكيده لاتين :
Focusing on out of plane buckling of three member y-shaped concentric steel bracings, 5 full scale one story one bay specimens have been tested in BHRC Structural Engineering Lab. The results show that inelastic buckling is the governing mode of failure. The buckling load of bracing increases by moving the convergence point towards the center of bay, while the story drift at buckling decreases by this geometrical change. Hysteretic energy absorption and damping of bracing increases by moving the convergence point towards the comer of frame. By reinforcing the bracing members and increasing the radius of gyration of brace sections, the hysteretic energy absorption and damping of bracing has been slightly increased.