The Washington State Department of Transportation (WSDOT) is updating its design methodology and detailing practices to facilitate optimized fabrication of precast, pretensioned concrete bridge girders. The objectives are reducing cost by saving on materials and labor, improving schedules by optimizing plant usage and production efficiencies, and enhancing quality by avoiding interferences and tight tolerances. Primary among these optimization techniques is the design and detailing of the permanent pretensioned strand configuration. This paper presents a step-by-step design procedure and example problem that optimizes the pretensioning configuration for maximum production efficiency while maintaining compliance with the applicable requirements for safe handling and shipping. The procedure provides the manufacturer with a high degree of flexibility in plant usage and production turnover.Other optimization techniques, while important, are not covered in this paper.
