I-35W bridge collapse

I attach an essay we wrote for a book that will be published by University of Minnesota Press titled "The city, the river, the bridge." The essay is a transcription of part of a public lecture I gave on infrastructure and on the bridge collapse.

After the bridge collapse there were several posts on Imechanica that included speculation about the cause of the collapse, including fatigue crack growth, lack of redundancy, etc.. Our investigation determined the collapse was a result of an undersized gusset plate that reached its plastic limit load.