Talk:Hart Bridge

Why is this bridge called a cantilever truss?
When I look at the pictures of this bridge, I do not consider it to be a cantilever truss. I would classify it as a three-span continuous, arch truss. To be a cantilever bridge, the truss must have a point of zero (or reduced) moment somewhere in the main span. I do not see this in the picture of the truss. The current version of the article contradicts itself. The text says if is a cantilever bridge, but the infobox says it is a continuous truss bridge. - SCgatorFan (talk) 22:35, 15 June 2008 (UTC)

Bridge type
This bridge is not an arch bridge. I am removing reference to this bridge type. The truss happens to form an arch shape, but there is no arch action supporting the structure. If you think this is an arch bridge, please provide a reliable engineering reference which states that before putting the text into the article. Several references list the bridge as cantilever truss, but this [site] has a database from FDOT that lists the bridge as continuous truss. As noted above, I visually consider the bridge to be continuous truss. This needs to be resolved or the discrepancy reported in the article. - ¢Spender1983 (talk) 18:19, 4 July 2010 (UTC)

This bridge is both a cantilever truss and a continuous truss. Cantilever trusses are a subset of continuous trusses. The articles for Continuous Truss Bridge and Cantilever Bridge that are linked in the above comment indicate this. The Continuous Truss Bridge article has a cantilever truss bridge photo as an example (the Lacon Bridge). The reason that the FDOT bridge database (actually part of the national bridge database) notes it as a continuous truss is that the database has no entry for cantilever. In the database record for this bridge the main span material code of 4 is for "steel continuous" and the main span design type code of 10 is for "through or pony truss". This was probably translated to "continuous steel Truss". It is correct that it is not an arch. The arch shape is because two characteristics of cantilever bridges are that the superstructure section is deep over the piers to efficiently develop the required negative moment and that the superstructure section over the channel tapers to save weight and to give the bridge a nice appearance. Bgtl (talk) 20:21, 24 May 2013 (UTC)