Hybrid simulation on semi-rigid partial-strength connections

Semi-rigid connections are considered neither completely pinned nor rigid. It is possible to control collapse mode and even the energy absorption capacity of frames during earthquakes. In this paper, (1) hysteretic behavior of end-plate connections subjected to cyclic and earthquake loading and (2) improvement of their rotation capacities are described. Two types of connections are prepared, extended and flush end-plate. Additional specimens of flush type are tested to improve their rotation capacities using high strength bolts with reduced shaft diameter. As a result, the capacity for plastic deformation of the connection is increased two times over those with JIS standard bolts. In case of bolt failure the rotation capacity is well predicted from the bolt elongation capacity.