This is a N Scale 104 ft. plate girder bridge.
The following are some of the abutment options. I knew what I needed for abutments so I printed the center and wings as one piece. Since I don't know what you need I broke the center and wings into separate pieces. If you need a wing on the other side mirror it in your slicer program if possible.
Here are a few pictures of the initial install on the layout.
Those openings in the walkway are a N scale 2” x 4 “ and the metal that makes up the grate is just a tad over 1 scale inch. That is all really small in N Scale. From the side of the layout you can't really see that the grating is open but still fun to print it and see what the printer can do.
More info on how the bridge was installed on the layout here......
https://1fatgmc.com/RailRoad/UP%20Canyon%20Division/page-208.htmlPrint files for the bridge and abutments here......
https://www.thingiverse.com/thing:6443837You can find all the files to 3D print this object and others on my thingiverse.com account here.....
https://www.thingiverse.com/sumner/designsSumner