| Single storey portal frame has been widely used recently due to its low steel consumption, fast construction speed, and good protection of environment. But the research on its seismic behavior is not enough, present design regulations of single storey portal frame only give some fundamental stipulations base on seismic behavior research of other structural systems. As its special property, such as permission of web buckling behavior and semi-rigid connection, is different from other structural systems, it is necessary to study on its seismic behavior.Test on three specimens of vertical end-plate beam-column connections was carried out in the paper firstly. The geometric similar ratio adopted was 1:2, cyclic lateral loading was applied at the transverse side of the connection with constant axial force. The specimens were designed in terms of present regulations by considering the influence of end-plate thickness, bolt strength. Test results showed that the failure focused on the upper flange buckling of beam with negligible plasticity deformation, the location of beam local buckling was about one and a half times of beam height from end plate; the specimen was strong enough in bearing capacity, but very weak in plastic deformation and energy dissipation; and the mate bearing capacity of connection raised a little with the increase of end-plate thickness and bolt strength.Secondly, numerical analysis model was established by finite analysis program ANSYS based on test results, in which large deformation, plane-plane contact of high strength bolt connection, elastic-plastic property of steel were considered. By comparing numerical results with test ones, it revealed that the maximum displacement at column top and bearing capacity agreed well. Moreover, the failure mode was similar. So the analysis model was effective for further parametric study. Finally, suggestions on design and on details were put forward based on test results, which can be referred in routine design.
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