Tunnel, Portal, Wings & Cribbing Design & Construction
Every Garden Railroad Needs a Tunnel! Ours is based on classic American wood timber tunnels. It’s a fancy design with portals, wing abutments, and log cribbing for the roadbed. Real log timber frames line the inside, attached to a durable hollow rectangular tube made of strong rot-proof composite decking material. Buried sturdy foundations supported the entire assembled structure above ground before we added the mountain. It even has interior incandescent lights in the ceiling.
Roadbed cribbing just outside of the tunnel has wood logs stacked like a log cabin. The cribbing was filled with rocks bigger than the ¾” gaps between the logs. The ballasted roadbed sits on top of the rocks. There are five Sub-Assemblies that make up the Full Tunnel Assembly: The Tunnel, The Portal, The two Wing abutments, and the Cribbing. All of these have their own buried foundations except the portals which do not need it because they’re screwed firmly into the end of tunnel. They are joined on-site in the railroad before we added the mountain.
Everything is made from redwood and composite wood for decking. Wood rots or gets eaten by termites when touching soil. I designed this so real wood does not touch any soil. All soil contact is with the rot-proof composite wood or silicone asphalt sealer. The tunnel is 14 years old and still looks perfect- even better than new I think!
Feel free to copy, use or modify any of the images and video shorts you see here. I hope this video shines a light at the end of your tunnel project. Good luck with yours! Thanks for watching, John Carmichael
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