Monolithic

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Image: Tunnel Opening Chart

Tunnel Opening Chart Barry Byers

Image: Step 1

Step 1 Barry Byers

Image: Step 2

Step 2 Barry Byers

Image: Step 3 & 4

Step 3 & 4 Barry Byers

Image: Step 5

Step 5 Barry Byers

Image: Step 6

Step 6 Barry Byers

Image: Step 7

Step 7 Barry Byers

Image: Step 7 Interior View

Step 7 Interior View Barry Byers

Image: Step 7 Interior View

Step 7 Interior View Barry Byers

Image: Step 8

Step 8 Barry Byers

Image: Step 9

Step 9 Barry Byers

Image:

Barry Byers

This is a diagram overlay of a typical 8’ square tunnel as compared to a 10’ wide by 8’ high air-formed tunnel. It is easy to see that the round tunnel is biggest (2’ wider) where it is needed. Any engineer can verify that the round shape is much stronger than the square. The round tunnel walls are 8" thick as opposed to 12" to 16" for the square. Even though it is wider, the total amount of wall and roof is about 15% less. Approximately 35% less concrete and reinforcing bars are needed in the construction.

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Barry Byers

The tunnel sides are perfect for pipe chases.

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Barry Byers

The Airformed tunnels are faster to construct and save on materials.

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Barry Byers

The tunnel can easily change directions. It can start above ground and dive under a building.

Image:

Barry Byers

The tunnel can also have other elements “molded” into it. These include drop chutes for material above to reach the tunnel conveyors.

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