The factors that govern the strength of a joint are:
Plate specification This will be of such a material and gauge as to successfully withstand tensile and bearing loads.
Rivet Specification This will be selected to withstand shear loads. In cases where the
specification of the rivet is not given, use a rivet of the same material as the plate, with a diameter
of 21/2 where T is the thickness of the plate.
Rivet Pitch This is important as too great a pitch will result in insufficient rivets to take the shear loads and too small a pitch will result in lowering the resistance of the plate to tensile loads.
Types of Rivet Spacing
Single Chain Used chiefly on attachment and lightly stressed joints.
Multiply Chain Used on watertight joints and in places of high stress where thick gauge plate is used.
Staggered Riveting Used as an alternative to multiple chain in watertight joints, circular patches etc.