原田 幸博

A reinforcing method of existing steel buildings by double-channel knee braces with only high-strength-bolted connections was already studied experimentally. The purpose of this study is to clarify how to model the beam-end and the knee-brace-end bolted connections for frame analyses. To discuss how detailed the connection modeling should be, parametric frame analyses of T-shaped and cruciform plane frames with the knee-braces were conducted, varying connection models (pin joints or semi-rigid ones with non-linear rotational springs). From the analytical results, overall behavior of the frame depends greatly on modeling of beam-end connections, less on modeling of knee-brace-end connections. By the frame analyses of steel buildings whose column members are H-section, it is also shown that the lateral stiffness of the weak-axis column plane frame with the bolt-connected knee-braces can be almost the same as the one of the strong axis column plane frame, if the knee-braces are long enough.