The bracing elements experience both tensile and compressive forces during an earthquake, however buckling is critical in bracing members. Buckling-Restrained brace (BRB) - in which the buckling is prohibited - have long been used in developed countries due to their high ductility and similar behavior in tension and compression. One of the improvements on this system is the use of BRB with reduced length rather than the whole brace as in conventional BRBs. The most unique advantage of this innovation is the independent selection of two parameters of stiffness and strength. Other advantages of reducing the length of buckling-restrained are reduced construction cost, flexibility in installation position, and increasing stiffness after yielding.
In this study the proposed reduced length BRB system is presented. Afterwards the advantages of reducing the length of buckling-restrained brace are introduced. The basics of seismic design of reduced length BRB frames are expressed. The comparative results of seismic design and time history analysis for BRB and reduced length Buckling-Restrained brace (RLBRB) are discusses. The results of the nonlinear analysis show better seismic performance of RLBRB in comparison to conventional BRB.