Buckling strength of welded and non-welded aluminium members.

High strength aluminium alloys when welded suffer a local loss of strength
due to heat-affected zone (HAZ) effects. The influence of such localised
strength loss on structural behaviour of columns, beams and beam-columns
is studied using numerical technique. Two programs INSTAF and BIAXIAL,
previously developed for the use of steel structures, have been modified to
incorporate the special features of the aluminium problem. The general inplane
behaviour of aluminium frames or members is studied by using program
INSTAF. The general 3-D behaviour of aluminium members is simulated by
the program BIAXIAL. Attention is given to the representation of the nonlinear
stress-strain behaviour of aluminium, in particular, its representation
in a form suitable for incorporation into numerical processes. Results are
presented for a wide range of problems to illustrate the severity of the HAZ
effect on the load carrying capacity of structural members.