Read an article about the Schaub variant truss.
Located just north of Oskaloosa, this unique deck truss bridge crosses the South Skunk River.
Built in 1901 to replace a previous, lighter bridge; this bridge a single unique deck truss span. Like many truss bridges along this route, this structure contains a unique design, which is considered to be a Schaub Variant truss.
The main truss has 6 panels with riveted connections. The bridge also features unique subpanels in four panels. The substructures of the bridge are made of concrete, and the approaches built of trestle approach. This railroad is the only route that had trusses of this design, making it a relatively unique design. However, this is the only bridge known to utilize the design on a deck truss.
Diagram of this style bridge
The Schaub variant truss is a take on the traditional Warren design, developed by Julius Schaub in 1901. While the original design featured a combination of pin and riveted connections, this bridge utilizes purely riveted connections.
The Schaub design offered a savings of material and a reduction of traditional stresses in truss members. Schaub considered it to be an ideal link between long pin connected spans and short riveted spans.
Overall, the bridge appears to be in fair to good condition, with little serious deterioration.
The author has ranked this bridge as being regionally significant, due to the unique truss design and large size.
The photo above is an overview.
| Upstream | IAIS S. Skunk River Bridge |
| Downstream | RI S. Skunk River Bridge |