Finite Element Analysis of Electro-Slag Welding for Diaphragms in Steel Box Column

• Main Author: 賴建霖
• Other Authors: 陳誠直
• Format: Others
• Language: zh-TW
• Published: 2007
• Online Access: http://ndltd.ncl.edu.tw/handle/10069774312062191315

碩士 === 國立交通大學 === 土木工程系所 === 96 === Electro-slag welding for diaphragms is the necessary welding procedure to build-up a steel box column which can resist bending in both axes of the cross section. Electro-slag welding (ESW) locates nearby the beam-to-column interface, and minor defect in the ESW could result in a brittle failure before plastic behavior is developed in the connection. Finite element analysis was conducted to study the effects of the ESW on the behavior of the connection through the investigation of performance indices, such as crack tip opening displacement (CTOD), stress triaxility, and rupture index. The results of the finite element analysis show that the parameters of the slit of the backing bars, melted radius of the ESW, and the eccentricity of the beam flange with respect to the ESW have little effect on connection behavior. However, a smaller distance between slit tip and the edge of the diaphragm due to the eccentricity of the ESW results in a larger CTOD that could be detrimental to connection behavior. The improved connections proposed after the Northridge earthquake, e.g., reduced beam section, rib-reinforced and widened flange connections, can be beneficial for enhancing the performance indices of the ESW.