The Rip Track

Can you tell me what's wrong with this HO scale bridge? Sure, on first glance, it looks like a fairly typical through girder bridge. But take a closer look. It's not completely prototypical. What's wrong with it? Read more to find out.

This picture should give you the answer...

The problem with this bridge is that it would not survive regular use on the prototype because the girders aren't straight. The natural tendency for a bent girder is for the girder to rotate to turn so the bend points downward. That means that a bridge like this one would not work if the girders were to actually carry any weight. It works here because the girders on the model are purely ornamental and it's the subroadbed (probably a piece of plywood cut in "cookie cutter" fashion) that is actually supporting the weight of the track, ballast and the trains that roll over it.