For folks that look at LOC/HAER
There is a set of pix for the Steel Bridge at Portland
It's about a decade newer than the Sims truss and in the pix you will see
fixed joints

ANd Pnoenix Bridge was the fabricator at Sims.
The smaller truss in the main hall at CSRM is also a Phoenix and sports the classic 'Phoenix' columns. It was on the SP branch between Radum and [brainfart]
Those are built up from six formed plates as to make a finned circular section.
Back around 1970 there was a similar bridge over the SP at Hercules that carried a 3 ft track down to a wharf- wonder if it endures.
And the last Phoenix notes- it built the SP viaduct over the Pecos near Langtry- later strengthened and still later replaced by the current one.
The most notorious Phoenix was the first bridge at Quebec, which failed during construction.
That led to basic testing of very large built up steel columns and new design rules for same.
The new design almost made it , but the center suspended span fell into the St Lawrence when being lifted [nearly] into place. Another was built and succesfully erected