Collection of sample design details that allow for the economical fabrication and erection of bolted splices, cross frames, and stiffeners. Provides engineers with design and detailing recommendations to help make steel girder type bridges more easily fabricated and. American Association of State Highway and Transportation Officials National Steel Bridge Alliance AASHTO/NSBA Steel Bridge Collaboration i Copyright © 2020 by the AASHTO/NSBA Steel Bridge Collaboration All rights reserved. Preface This document presents guidelines developed by the AASHTO/NSBA. Girder bridges are structurally the simplest and the most commonly used on short to medium span bridges. 1-1 shows the Central Viaduct in San Francisco. In this chapter, straight composite. The “fit” or “fit condition” of an I-girder bridge refers to the deflected girder geometry associated with a specific load condition in which the cross-frames or diaphragms are detailed to connect to the girders. Provides material, geometry, analysis, and design requirements for curved steel plate girder units. It covers topics such as span arrangement selection, basic framing development, cross-frame/diaphragm selection, girder design, and detail design issues. The guidance is intended to help bridge engineers make knowledgeable.