Seismic performance assessment of eccentrically braced steel frames with variable-cross-section horizontal shear links

Based on the principle of web weakening, two types of variable-cross-section shear links for horizontal eccentrically braced steel frames (H-EBFs) were analyzed in this study. In the first design, an I-section link (L2) was designed with a lower web and wider flange than that of an ordinary shear link (L1), and in the second design, an I-section link composed of two small I-section beams (L3) was designed. To study the seismic behavior of the two types of H-EBFs, cyclic loading tests were performed on three scaled specimens, L2 (H-EBF-L2), L3 (H-EBF-L3), and a traditional link (H-EBF-L1). The results showed that most of the inelastic actions of the three specimens were concentrated in the shear links and that the failure modes were similar. Compared with specimen H-EBF-L1, the links of specimens H-EBF-L2 and H-EBF-L3 had better deformability, and the bearing capacity of the frames also improved simultaneously; thus, the energy-dissipation mechanism of H-EBF improved. The material costs of specimens H-EBF-L2 and H-EBF-L3 were reduced to a certain extent, realizing economic benefits. Additionally, the numerical models of the three specimens were established. The modeling results were in good agreement with the test results, and it was verified that the model could accurately simulate the loading process of the tests.