Bridge Types

What is a bridge? A bridge could be anything as simple as a log laying across a creek. Or as sophisticated as the Golden Gate Bridge. A bridge is just something that helps us cross an obstacle, whether that be a river, ocean, swamp, canyon, or highway. At the most basic level, there are three types of bridges: Beam, Arch, and Suspension.

Truss Series: Howe Truss

The Howe Truss was designed by William Howe in 1840. It used mostly wood in construction and was suitable for longer spans than the Pratt truss. Therefore, it became very popular and was considered one of the best designs for railroad bridges back in the day. Many Howe truss bridges exist in the North West United States, where wood is plentiful.

Truss Series: Pratt Truss

The Pratt Truss was designed by Thomas and Caleb Pratt in 1844. It became popular for railway bridges because it was able to have long spans. The Pratt has many variations, most with their own unique name. For instance, the Baltimore, Pennsylvania, and the Parker are all based off the Pratt.

Truss Series: Warren Truss

The Warren Truss was patented by James Warren in 1848. It has been around a while. It is one of the most popular bridge designs and examples of it can be found everywhere. The Warren Truss uses equilateral triangles to spread out the loads on the bridge. This is opposed to the Neville…

Video: Build A Model Bridge

This is the absolute best video I have seen about building model bridges. Roy Coleman, the founder of the International Bridge Building Contest, gives a very informative presentation in this video. The presentation is over an hour long. He shows how to build a bridge from scratch. He is gearing his video towards the…

Elevated Bridge

Science Olympiad is bringing back the Bridge Building event in 2009, except in a modified form. The event for ’09 is Elevated Bridge, which will provide an interesting and refreshing challenge. The draft rules that soinc.org are very interesting and make for a good read. Check them out as the new bridge event looks to … Read more

Truss Series: K Truss Analysis

The K Truss design was a variant from the Parker truss design. The Parker, in turn, came from the Pratt truss. The idea of the K truss is to break up the vertical members into smaller sections. This is because the vertical members are in compression. The shorter a member is, the more in can resist buckling from compression.