Structural response of Aluminium T-Stub connections at elevated temperatures and fire

Many aluminium structures contain welded and bolted connections that are modeled as one or more equivalent T-stubs – also referred to as tension zone components – for the structural assessment. Knowledge on the structural behavior of such T-stubs is thus essential for proper designs. However, this behavior has never been checked for fire conditions. In this paper, the structural behavior of aluminium T-stubs exposed to fire is studied through a combination of tests, finite element simulations, and theoretical models. A safe and conservative assessment procedure is developed for determining the critical temperature, based on the material deterioration as a function of temperature. This enables engineers and practitioners to determine a conservative value of the fire resistance.