1. Research Images (Bridges)

Here's an example of a truss bridge. Some of these beams are under tensions and some are under compression. I'd like to use something like this design for my bridge. I'll probably need a more rigid / complex structure under the roadway as well.

Corrugated cardboard is quite rigid and strong given its light weight. I hope to use something like this for my roadway. Posibly even for the top of the bridge to keep it from buckling. I'll need to sort of fashion my own corrugation via accordian-like paper and laminant on top and bottom.

Here is a triangle beam. It seems to be way stronger than a square beam, but not as strong as a cylindrical beam. However, it terms of assembly, I think this will be way easier to glue onto other beams.

I thought this type of beam could combine the strength of a cylindrical beam with the ease of connection of a triangle beam. However, it may be a bit tedius to make. Maybe a rectangular collar would be better, as it allows for connecting on multiple sides.

I have also considered how to keep my top cylindrical beams joined to one another. This joint here could be made at a 30 degree angle (or any angle) and folded together in a sort of origami way.