변단면 철골 보-기둥 용접접합부 응력전달경로의 해석적 재검토

Employing elementary bending theory for the design of welded steel moment connection has been brought into question by several researchers since the 1994 Northridge and the 1995 Kobe connection failures. The basic bending formula was thoroughly re-examined in this study based on finite element analysis of tapered beam-column connection. The results of this study confirm that the shear transfer mechanism in the connection is completely different from that predicted by elementary bending theory; the shear stress distribution is different from the prediction of element bending theory in the tapered region. Influence of the boundary condition effects was obvious within the distance of 0.5d from the column face, where d is the beam depth. Also, as the ratio of tapered height to the length of tapered section increases, the shared rate of shear stress on the beam flange decreases by 25-30%, which suggests that the unfavorable stress concentration in the beam flange can be reduced.