V15T_26- Evaluation and Rating of Bridges

The need for bridge evaluation and rating is discussed. AASHTO legal load types are presented. The definition of a rating factor is introduced. Three methods included in the AASHTO Manual for Condition Evaluation of Bridges are presented. They include rating based on allowable stress method, Load Factor Design (LFD) method and Load and Resistance Factor Rating (LRFR) method. The rating procedure is demonstrated for a steel girder bridge, a prestressed concrete girder bridge. In addition, the rating procedure is demonstrated for a partially damaged prestressed concrete girder bridge. "Evaluation and Rating of Bridges" is the last of the four courses in the Bridge Design and Evaluation series. The series objective is to present the approach to design and evaluation of highway bridges. The design is based on the AASHTO LRFD Code and evaluation on the AASHTO Manual for Condition Evaluation of Bridges. The presentation includes the design philosophy, procedures and practical examples.