If we were to do this, I think it would be
neat if we could actually construct the bridge sections as bridges.
We could have 5 individual bridges (welded/bolted
together so they move in unison) that are supported from underneath (ala photo
1, but with more of an erector set feel for weight purposes).
Or we can do an erector set style lift
bridge (6” on each side of the module with the towers, and 36” lift
section) similar to the cape cod photo attached. This would benefit the
layout as far as torsion is concerned. Again, individual trusses, but
attached so they lift as one. It could be motorized or manual with a
counter weight assembly inside the towers. The only drawback to this is
that it would have to be a 40” lift. (assuming we would want 6’ walk
under clearance).
Isn’t one of our members a civil
engineer? Maybe he can help with design and/or guidance.
-Mike
