Westbound Lincoln Highway
This photo was taken during the 90th Anniversary Lincoln Highway Cross Country Cruise.
Photo taken by J.R. Manning in August 2003
BH Photo #148592
Fmiser,
You are correct in that this truss is a Parker and not a Pennsylvania. I can understand some confusion due to the stiffening struts through the middle to the truss web members.
The data for this bridge state it is a Pennsylvania truss. As I understand, a Pennsylvania would have half-length diagonals and verticals connecting to the lower half of the full-length diagonals. I don't see any. Thus I think these are actually Parker trusses.
So, I'm changing the "Design" to Parker. If I'm wrong, slap me and change it back. :)
This bridge is the longest vehicular truss bridge in the state that does not cross the Missouri River. The previous bridge here was a multi-span pin-connected Baltimore truss bridge. One of those spans remains because it was moved here: http://www.bridgehunter.com/ne/sheridan/C008124905P/
I agree with Mr. Goff. Some have argued that a Parker with stiffening struts automatically becomes a Pennsylvania, (In need to relocate the source) but I have never thought of it that way. Of course, I am not a bridge engineer, so I am hoping to hear some other opinions on that matter.