Shear lag in tension member welded connections

The authors attempt to validate an analytical method proposed recently for calculating the reduction in strength due to shear lag effects in tension member welded connections. The analytical method is based on an assumed distribution of forces along inclined lines in the member ends, somewhat similar to the Whitmore's concept used with gusset plates for bracing members. The stress distributions at the end of a flat bar welded to a gusset plate are examined at various load levels using non-linear finite element analyses. Three different values of the ratio of the weld length to the width of bar are considered. Results are presented regarding the distribution of shear flow along the length of the fillet welds, the von Mises stress distributions and principal stress patterns in the tension flat bars, as well as longitudinal and von Mises stress distributions at various sections along the bars. The strength of the connections predicted using the finite element models is compared to that obtained with the analytical method and from current CAN/CSA-S16-01 design guidelines. Recommendations for further research are made.