Da Vinci Arc?
The unique structure of this bridge holds itself together without any fasteners or connectors. The parts are notched for easy assembly, just slip the notches together and build this sturdy bridge in a matter of minutes. Take it down and rebuild it again and again. The longest pieces are only ten inches long, but when assembled, this bridge spans more than three and a half times that distance.
It's a combination of arch technology and a shallow-truss type technology - a truly ingenious system of interlocking forms. Each form supports the two segments adjacent to it in a daisy chain of mutual support, with only the two end segments touching the ground.
This is da vinci arc how looks alike
To stabilise and get the strong one, put truss to sustain load.
The final view of our bride. Civil's Girl bridge
Guess what? We got 1st place for this competition.
Material : Balsa Wood, Glue stick, Glue gun
Load applied : 280 N = 28 kg (not much exactly)
Deflection = 5mm
Condition of bridge : Just a little bit crack