Long-span bridges are often used in environmentally sensitive terrains, water crossings, and in locations with traffic and geometric restrictions.
The TRB National Cooperative Highway Research Program's NCHRP Research Report 994: Use of 0.7-in. Diameter Strands in Precast Pretensioned Girders presents the design methodology for precast pretensioned girders using 0.7-in. diameter strands based on comprehensive analytical and testing programs. The use of 0.7-in. diameter strands would help bridge designers extend the spans of the existing girder shapes. The report is available on the Transportation Research Board web site at https://www.trb.org/Main/Blurbs/182723.aspx