Welded Connections

Fillet welds and butt welds are widely used in construction. They represent 80% and 15%, respectively, of all welds found in structures. For the remaining five per cent, plug and fillet all round welds are mostly used. Butt welds are used between adjacent plates in so‐called butt and tee‐joints. Contrary to a butt weld, a fillet weld requires no preparation of the plates to connect. This is an important feature in terms of fabrication costs. Fillet welds are applied to the surface of the connected plates; they exhibit an approximately triangular shape. Fillet welds all round is a term used to describe fillet welds in circular or elongated holes. For weld design, three fundamental assumptions are usually made: the welds are homogeneous and isotropic; the connected elements are rigid and their deformations are negligible; and only nominal stresses due to external loads are considered.