Abstract
The authors developed the frame constructed by RHS column to vertical haunch-beam connections using external diaphragm with high strength bolts. This frame is possible to re-use by means of connecting to column and beam using hi-tension bolts. For the purpose of comprehending the performance of this frame, we performed cyclic loading tests for column-to-beam connections. As the result, it is clarified that 1) the stiffness of vertical haunch-beam is possible to evaluating by divided three elements of parallel shape, tapered shape of haunch, and central element, 2) the stiffness of beam-column connection is necessary to evaluate influence of deflection due to bending and shear, 3) the strength by yielding haunch plate is possible to evaluate by increasing progressively truss corresponding to bending and shear, 4) it is necessary to control yield and local bucking of haunch plate for ensuring enough deformation capacity in this frame, 5) it is possible to improve deformation capacity of this frame by equipping several vertical stiffeners at end of haunch in yield region, particularly vertical stiffeners is effective in case of large depth.
