Toothpick Bridge Designs - Truss Bridges
A common bridge design was the Warren truss bridge patented by James Warren and Willoughby Monzoni in 1848. The diagonal braces of this design point both towards and away from the midpoint of the bridge. Thus they experience both tension and compression stresses as a load, such as a trains, crosses from one end to the other.
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The Howe Truss Bridge (designed by William Howe ) was patented in 1840. The advantages of the Howe Truss Bridge to the railroad companies of the era were that it was easy to prefabricate offsite and to ship by rail.
When building your toothpick bridge using the Howe Truss, be sure to use crossing members to give it strength. Variations of this crossing member design are easily located on the internet. |
As you can see, the Baltimore truss bridge is a simple modification to other standard truss bridges. The smaller struts have been added to increase the support and improve the load distribution across the structure. When building your toothpick bridge, be sure to glue the smaller struts perpendicular to the main cross beam.
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