ABSTRACT
In this paper, in order to discuss aseismic capacity of semi-rigid frames under actual earthquake wave, the earthquake response analyses for three-bay four-story frames were conducted with three combinations of mixed use of rigid and semi-rigid connections. Here, four kinds of actual seismic waves were inputted: El Centro NS; JR Takatori EW; Taft NS; and Golden gate EW earthquakes. The dynamic response characteristics of these steel frames such as fixed-end moment, base-shear force and displacement of frame were discussed. Semi-rigid connections were represented by using discrete rotational springs with nonlinear connection stiffness which were given by using a three-parameter power model, and whose hysteretic momentrotation relation was assumed following an independent hardening rule, for simplicity. From this study, following results were obtained: 1) maximum bending moment and shear force can be reduced by proper combinations of rigid and semi-rigid connections, and 2) semi-rigid connections may be able to be used for tall frames accompanying with rigid connections in the countries with frequent earthquakes.
