Stress Analysis and Design of Double Fillet-Welded T-Joints

摘要

The stress distribution in double fillet-welded T-joints was investigated with a computer modeling technique. The finite element method was used for the analysis of T-joints in the plane-stress condition, under static load. Photoelastic stress analysis was employed to check the validity of the computer calculations. To address the design aspect of the stress analysis, the American Welding Society (AWS) welding design procedure was followed, and the AWS permissible design loads were used as a reference for the stress analysis. The ultimate strength of the T-joints was determined when the plastic hinge first occurred in the weld joint as the applied load progressively increased. Design curves for the double fillet-welded T-joints with various degrees of flange flexibility were obtained. These design curves were compared with the AWS D1.1 design code and the American Institute of Steel Construction Specifications (AISCS). As a result of this comparison, a design concept and procedure for the double fillet-welded T-joints was conceived. To determine the weld performance with respect to the joint strength, the full-strength weld size was evaluated with different web lengths and flange flexibility in accordance with the AWS and AISC design procedures. It is suggested that the industry may have reached a point where improved weld design procedures may be incorporated for a more efficient joint design.