American Association of State Highway and Transportation Officials (AASHTO)

The American Association of State Highway and Transportation Officials (AASHTO) advocates transportation-related policies and provides technical services to support states in their efforts to efficiently and safely move people and goods. Individual US states typically adopt AASHTO guidelines, sometimes with modifications to reflect local practice.

Bridge Design Codes

 * AASHTO Standard Specifications for Highway Bridges, 17th Edition, 2002
 * AASHTO LRFD Specifications for Highway Bridges, 3rd Edition, 2004