| Both the steel frame and eccentrically braced frame use a part of the frame beams to yield then dissipate the seismic energy,which has good ductility and energy dissipation capacity.However,after the earthquake,the damaged frame beams make it harder to repair the structure.The shear link,which have the flexible size selection are connected to the frame beam by end plate bolts.In order to achieve recover the structural function after the earthquake rapidly and reap a good socioeconomic performances,we choose the rational design of shear link,which can concentrate the damage on the replaceable shear link.In this paper,the seismic performance analysis of steel frames and eccentrically braced steel frames with replaceable shear link are carried out.The main contents are as follows:The finite element software ABAQUS is used to numerically simulate the reciprocal loading test of replaceable shear link and eccentrically braced frames in related literatures.The reliability of finite element modeling method is verified by comparison with experimental results.A refined finite element model of two-story single-span frame with shear link was established to carry out the monotonous pushover analysis and reciprocating loading analysis.The performance of the common frame and dog-bone connection frame were compared and analyzed.Based on the variation of the size and material strength of the replaceable shear link,the influence of the plastic bending moment ratio of the shear link and the frame beam on the seismic performance of the frame are studied.The result shows that the structure has obvious yielding sequence by setting the shear link in the frame structure.There is a large displacement difference between the complete yielding of the shear link and the column legs,which makes it easy to replace the damaged energy-dissipating components.The performance of a common eccentrically braced frame and a two-story single-span frame with replaceable shear link are compared and analyzed.The result shows that there is no significant difference between initial stiffness’ s two models.Although the replaceable shear link yielded earlier,but the moment when the frame legs yield is later than the ordinary eccentrically braced frame.In order to achieve the end plate bolt connection,the cross section of the replaceable shear link is small,which makes the ultimate bearing capacity of the structure is smaller than the ordinary eccentrically braced frame.The parameter analysis of eight eccentrically braced frames with replaceable shear link are carried out.The parameters include the length of the shear link and the ways of arranging eccentrically braced.The result shows that the performance of the shear-type shear link is better than the curved-type shear link.The performance of the K-type and V-type eccentrically braced frames are superior to the single-slanted eccentrically braced frame.A 12-story common eccentrically braced frame and an eccentrically braced frame with replaceable shear link were designed for response spectrum analysis,dynamic time history analysis and pushover analysis.The seismic performance and failure modes of the two frames were investigated and compared.The result shows that the shear link on the upper part of the common eccentrically braced frame structure are difficult to yield.As there are more options of selecting the cross-section of the replaceable shear link,therefore,except for the top layer,the shear link of other stories are yield.The plastic energy dissipation capacity of the shear link is better than the common eccentrically braced frame during the large earthquak.Because of the cross section of replaceable shear link’s section is smaller than the ordinary energy-dissipating beam’s section,it has a certain influence of the ultimate bearing capacity on the two-story single-span model,but less on the overall structure of 12-story. |
