Eccentrically braced steel frames (EBFs) dissipate energy by shear or bending deformation of links [1][2][3] and have different structural forms based on brace arrangements, including K-type, D-type, Y-type, and V-type [2,[4][5][6][7][8] , as depicted in Figure 1. Links of Y-type eccentrically braced frames (Y-EBFs) are located outside beams, and the plastic deformation is isolated to the links rather than the other members that are in an elastic state.The links are easily replaceable after an earthquake. [9][10][11] The non-energy-dissipating components are designed to be larger than required, to ensure that the links have sufficient plastic deformation capacity. This deliberate overdesign limits the common use of this structural form (JGJ 99-2015). Although the frame beams and columns can be used as high-strength steel (HSS) to reduce material costs, the increased strength of HSS will lead to an increase in the yield strength to tensile strength ratio and the deterioration of elongation. [12] The mandatory requirements of steel in China according to the "Code for seismic design of buildings GB50011-2010 (in Chinese)" are the ratio of measured yield to the strength of the steel should not be greater than 0.85, and the steel should have a visible yield plateau. In addition, the elongation should not be less than 20%. This mandatory rule limits the application of HSS (the nominal yield strength is not less than 460 MPa, f y ≥ 460 MPa) in seismic precautionary areas (GB50011-2010). EBF structures with HSS are proposed to solve this problem. The links are made of ordinary steel (f y ≤ 345 MPa) with excellent deformation capacity, but the frame beams and columns use HSS (f y ≥ 460 MPa, such as Q460 and Q690). The plastic deformation is isolated to the links to ensure that the structure has good energy-dissipating capacity and ductility during an earthquake, and the beams and columns remain in elastic. The non-energy-dissipating elements do not require excessive plastic deformation, and HSS can be used. [13,14] Models of 5-story, 10-story, 15-story, and 20-story were designed using the performance-based seismic design (PBSD) method with both HSS and ordinary steel Y-EBFs. The PBSD method makes use of base shear and plastic story shear distribution under earthquake conditions, as well as the predicted failure mode of the structure, that is, all links in the elastic-plastic state to dissipate energy and that the other components remain in elastic. The distribution of the story drift is uniform, and there is no clear weak story [15][16][17] . Therefore, they have the same performance objectives, bearing capacity, failure mode, and story drift distribution. The seismic behavior of Y-EBFs is studied by static pushover and nonlinear dynamic analyses.
| TEST AND FINITE ELEMENT VERIFICATION
| Specimen size and loading systemFour single-story single-bay 1:2 scale Y-EBF test specimens were used by HSS. Each was 1.8-m high, 3.6-m wide, and the length of shear links in Y-1 and Y-2 were 300 mm (ρ = e/(M p /V p ) = 0.88) and 500 ...
