The Theory chapter explains the assumptions and procedures used in Precast/Prestressed Girder. It is divided into two sections, AASHTO LFD and AASHTO LRFD. Each section covers the topics related to the respective design code. Please refer to the appropriate section as needed.

Note that Precast/Prestressed Girder has the ability of dual codes, that is, the user has the option of using either AASHTO LFD or AASHTO LRFD design code, in accordance with the AASHTO Standard Specifications for Highway Bridges, Seventeenth Edition, 2003 and AASHTO LRFD Bridge Design Specifications, sixth Edition, 2012, respectively. Refer to the References section for additional information.