Southern Street Railroad Overpass

This bridge ranks among the most unusual bridges I have ever seen. First off, the bridge is a continuous three span structure.  A simple span bridge means that separate individual bridges connect the piers on a crossing. With a continuous span, the bridge has the appearance of a single span crossing, although there may be piers holding this span up in between abutments. Compare this to the CSX Bridge in Monroe, which is a simple three span structure. The bridge is a nine panel warren through truss, but because it has an odd number of panels, they had to get creative with a panel near the west end of the bridge. Note the two diagonals forming an 'X' in the above photo. Other than this, the rest of the bridge is a normal subdivided warren truss with riveted connections. The next unusual thing about this bridge is that it is really two bridges sitting right next to each other. Both bridges were built at the same time, and so each span is identical. They sit very close to each other. Portal bracing is a large v-laced design Lattice is present on the rest of the bracing for this bridge. Lattice is also present on some diagonals and under the top chord, but the lattice is segmented by unusual angle sections. I have seen this on other railroad truss bridges, but it is still uncommon. These angle sections give the bridge a rougher appearance. Another odd thing about this is the shear size of the bottom chord of this bridge. Usually the bottom chord is less massive than the top chord, but that is not the case here. I am unsure why the bottom chord is so massive. Even the builder is unusual, at least here in Michigan. The plaque on the bridge credits the McClintic-Marshall Company of Pittsburgh, Pennsylvania with building the bridge in 1930. Perhaps the only thing not unusual with this bridge is the supports. It sits on concrete piers and abutments. The feet on the bridge are weird however, as they are very tall.

Overall this is a fascinating bridge, and I am glad it is on a railroad, as I doubt it will be going anywhere. The bridge is so massive you could probably let it rust for a couple centuries and still drive a tank across it!

This bridge is also the only truss bridge railroad overpass in Michigan.