A W6×12 is strengthened with a 3 4 -in -by- 3 4 -in. bar welded to its top flange as shown. Because of the weld used, the horizontal shear stress at the connection between the bar and the flange cannot exceed 4.0 ksi.
In the web, the shear stress is limited to 20 ksi. Use the general shear formula to determine the allowable vertical shear force on this cross section.
