Autodesk Labs Software Developer, Gyorgy Ordody, submitted this.
As we now know in the Bay Area, it’s not easy to maintain and build bridges. We have the Bay Bridge (or James "Sunny Jim" Rolph Bridge) trouble going on as this is being written (http://www.sfgate.com/cgi-bin/article.cgi?f=/c/a/2009/10/30/BAU91ACT27.DTL&tsp=1), while the new eastern span is being built. In fact, the Autodesk Gallery (http://usa.autodesk.com/company/autodesk-gallery) has a model of the new span, as you could see in a previous post (http://labs.blogs.com/photos/autodesk_gallery_at_one_m/bay_bridge_jpg.html). For more about the new eastern span, you can check out http://baybridge360.org/ while you can see a panoramic view of the actual Bay Bridge here: http://bata.mtc.ca.gov/bridges/sf-oak-bay.htm.
The Golden Gate Bridge is also continuously maintained, painted and the lane configuration are changed several times a day to accommodate the traffic. In fact there are plans to implement a “zipper-like” solution for that problem (http://www.goldengatebridge.org/projects/mmb_aug08.php).
Other bridges are also being earthquake retrofitted (http://www.mtc.ca.gov/news/transactions/ta1205-0106/rsr.htm, were widened (http://bata.mtc.ca.gov/bridges/sm-hayward.htm) added to (http://bata.mtc.ca.gov/bridges/ben-mar.htm) replaced (http://bata.mtc.ca.gov/bridges/carquinez.htm).
To learn about these bridges, check out the Bay Area Toll Authority page: http://bata.mtc.ca.gov/bridges/index.htm and the homepage of the Golden Gate Bridge: http://goldengatebridge.org/ (which is under different jurisdiction from the previous ones.)
To build bridges is not easy. To start to warm up to the idea, you can just play (highly addictive) games. The grandfather of all bridge building games is Bridge Builder. You can learn more about this game/download it from a fan page, check out: http://www.bridgebuilder-game.com/ or http://www.stopgeek.com/featured-download-bridge-building-game.html You can also buy it its (3D) sequels at the source: http://www.chroniclogic.com/
The popularity and addictivity might be due to the (mostly) realistic physics, and the ability to test the bridges with actual traffic on them. In fact, there is even a wiki page about them: http://en.wikipedia.org/wiki/Bridge_Builder, where you can learn that among many others, the equally addictive and physics based Word of Goo (http://www.2dboy.com/games.php) and Armadillo Run (http://www.armadillorun.com/). And while you’re sitting in traffic, waiting for the Bay Bridge-related traffic jams to clear, you can play a Bridge Builder clone on your phone! (Actually, please don’t do that.)
After playing these games, only a few years of college and practice separates you from designing real bridges! And if you do so, maybe you’ll use Civil 3D. And maybe there will be an add-on to Civil 3D that will help to model those bridges. So, check back to the labs webpage at http://labs.autodesk.com to see if there are any new tools in the coming weeks.