Jeffers, those photos should keep you busy for a while!
I am struck by the absurd thinness of some of those gusset plates. They appear to be ~20% as thick as the width of the rivet heads. In places they look like torn paper...
Jeffers, look at the overhead, pre-collapse view of the bridge. Could live-load lateral thrust from traffic on that curve leading to the south end of the span have caused the lateral deflection/bending/failure that we see?
Too bad that NTSB report is a PDF. That prevents us from live-linking to specific photos for discussion. Even worse, they didn't even number the figures; that makes it extremely difficult for us to "stay on the same page"... :-(
False alarm on post collapse paint. Apparantly, both U10 east facing gussets failed identically, the west one and the east. Hard to believe, but the tears are identical, right down to the folded over triangular flaps, at the U10 end of L9-U10 East and West.
No coverup.
My mistake, apologies for confusion.
There is a wealth of data in that PDF.
It will take time to look through it all.
You are welcome! There was heavy construction material piled up on the south end on the west side. I’m guessing that was the proverbial “straw” that broke the camel’s back.