Fatigue Behaviour of Aluminium Members with Different Notch Root Shapes

In unitised curtain walls, the transfer of horizontal loads, mainly wind loads, from the upper into the lower unit is achieved through the head/notch interlocking connection. Optimisation of the machining process would require a sharp root of the notch, causing an increase in the stress concentration. In order to predict fatigue resistance during design life, the influence of the radius at the root of the notch has been tested in both static and cyclic regimes. The cyclic regime is based on the load history equivalent of 50 years of wind exposure. Numerical simulations on the test assembly have been conducted in order to verify their adequacy for future research on similar issues. The experimental results demonstrated that, for the given specimen shape and alloy, a sharp notch would not lead to premature failure, and such a detail is safe from the purview of damage-tolerant design.