`Australian aluminum bridge doubler plate failure`

Brief mention as a famous fatigue failure from wrap-around doubler-plate weld details, ~50–60 years before lecture.

The aluminum design manual has all kinds of connections, bolted or welded, in different categories A through F if I remember. The E categories are not quite as bad as F, but things where you wrap a weld around and you have lots of residual stresses, you end up getting fatigue cracks fairly easily. There are some famous bridge failures that occurred because of that type of doubler-plate design where they wrapped around. There's one in Australia that was a big surprise about fifty or sixty years ago to the designers of steel. A lot of those details have come exactly out of the steel construction manual in terms of weld-type details, but they apply to aluminum in a lot more complex ways.