Vancouver, British Columbia
The bridge I made is modelled after a Leonardo da Vinci designed self-supporting arched bridge. I used structural 4x6 fir beams and red cedar for the bridge deck, rails and post. Joints are birds mouth and through doweled with 1" hardwood (no glue). All the wood was cut from our property that can only be reached by boat. The property is totally off the grid. Electricity is from a water powered Pelton wheel, solar panels and generator backup. I used a Woodmizer and an Alaskan 50" chainsaw to mill the boards and beams. The bridge spans 27' at the base and has a 34' deck. I am in the process of having an engineer give me the load capacity of this bridge. It was a lot of fun building.
Leonardo da Vinci's design