Experimental investigation of steel structure with innovative H-type steel unbuckling braces

摘要

>SUMMARY class="section" id="tal1108-sec-0001">The unbuckling brace, acting as a combination of a conventional brace and displacement-dependent damper, can successfully avoid the bucking and consequent fracture compared with the conventional brace, which has been widely applied in concentrically braced frame structures. In this paper, the H-type steel unbuckling brace (SUB), which is welded by steel flats and core made of low-yield steel, is presented. The quasi-static tests, the shaking table tests of a steel structure with SUBs and conventional central braces and the numerical analysis of a real steel building with and without SUBs are conducted in this study to evaluate the performance of SUBs. The results demonstrate that the SUBs have excellent plastic deformation capacity, stable energy dissipation capacity and no stiffness degradation, and can provide certain initial stiffness to the structure and dissipate earthquake input energy by yielding behaviour. Moreover, it is effective in reducing the structural response, and in particular, in controlling the structural displacement. In conclusion, the SUB proposed is a lateral resistant member with high stiffness and strength and an excellent energy dissipation device, which is much more competitive than the conventional brace in improving lateral resistance and seismic performance of the frame structure. Copyright © 2013 John Wiley & Sons, Ltd.