Effect of Beam Splicing on Seismic Response of Buckling-Restrained Braced Frames Effect of Beam Splicing on Seismic Response of Buckling-Restrained Braced Frames

by Prinz, Gary S

The deformation capacity of typical buckling-restrained braced frames (BRBFs) is limited by the rotation capacity of connecting regions. The rotation capacity of the connection region is limited by fracture of the gusset welds and yielding in the beams and columns. A different connection detail with beam-splices outside the gusset has been shown to increase connection rotation capacity when compared to typical connections, in a few component tests.

This study expands upon the performed component tests, by analyzing the beam splice connection at the system level under directional dynamic loads. Finite element analysis and dynamic loads are used to analyze two 3-story frames having different connection configurations. The first frame has typical BRBF gusset connections, while the second frame has BRBF gusset connections with beam splices. The two frames are dynamically loaded using a recorded earthquake ground acceleration applied at three directions, relative to the frames, and the performance of each frame is compared.

Results indicate that the connections with beam splices effectively prevent large moments from accumulating in the connection regions, reducing gusset stresses. In addition, the use of beam splices more uniformly distributes the brace load into the beams and columns, and has little effect on in and out-of-plane story drift.