Yesterday we finally laid the last of the sub-roadbed and base for some industries. I promised some pictures of the 3 section bridge area and early attempts at bridge trusses and tunnel portals.
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| Outside view of the curved bridge. |
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| Inside view of the curved bridge. |
As
I stated before, a curved railroad bridge is really nothing more than a
series of straight spans wide enough to allow the car overhang to clear
the sides.
Originally
I thought of using a through girder bridge, but decided that a through
truss bridge would be an artistic touch and allow the viewer to see
through the area into our proposed mine location.
The inside view shows the mine access track sub-roadbed (black.) The track radius is 23" so using the 7" length truss on the outside will require the inside trusses length to be determined by the line from each end of the truss to the center point of the 23" radius. The support beams will coincide with those four lines, extending out to clear the lower track. It will become clearer as it takes shape.
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| The original Atlas truss bridge that was the inspiration. |
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| First try at a foam-core board tunnel portal. |
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| My original 7", outside truss. 3/32" square strip wood. |
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