Basic Connections
Butt Joints - Double Shear
The video below shows how a butt joint acts in a situation of Double Shear. When the joint is pulled apart due to tensile forces acting on the primary member, the joint can fail in one of two ways. Either the bolts can shear in two planes (indicated where they glow red during the animation), or the plate material can pull through if the amount of steel between the bolts and the edge of the plates is insufficient to resist the tensile forces. Resisting this sort of pull through shear will require that there is adequate thickness of plate material as well as distance from the edge of the plate.
This type of Tension Splice is often to be found on the web members of beams that must be spliced. Placing the plates on both sides of the web assists in evenly tranferring the forces as well as reinforcing the connection against any deformation due to potential lateral forces (coming in from the side).
