I wondered more about the ties than the bridge structure. If the beams were placed beneath the SG rails, then a SG train would only put the ties in compression, but a NG train would be trying to snap the ties close to the center. It may be that the track structure is plenty stroug enough to handle the load, but I wondered.
And I did know about turntables having four rails, but I always thought it was because there's no good way to line up a 3 rail turntable when you rotate it 180 degrees.
Everett Lueck Wrote:
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> Any bridge that could handle a centered standard
> gauge load, could surely handle a slightly off
> center narrow gauge load (at half of the weight).
Kenneth Rickman
Researching and modeling the Danville & Western Ry.
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