I'm convinced -- I'll accept that it's probably a wide-flange. But Mike, in fact it would be VERY uncommon for a heavy truss like this to be made up of flat stock. I say that as a licensed architect who had graduate-level courses in structural design and who works for an engineering firm that designs and inspects ... bridges.
I didn't realize that this was on the approachways to the bridge proper, and is thus significantly larger than what I've seen.
What I described was apparently an older style construction technique for short span bridges (think across a culvert or stream, not across a major river). I saw it in a number of 1930s-era bridges in Central Pennsylvania.
Saw them when I was doing structure photography for my Father, who was a civil engineer and was inspecting bridges.
That bridge in New Jersey is actually mild compared to some of the things I saw... Or in the case of badly degraded bridges, didn't see...