The use of precast pretensioned girders using 0.7-in. diameter strands would help bridge designers extend the spans of the existing girder shapes.
The TRB National Cooperative Highway Research Program's NCHRP Web-Only Document 315: Details of the Study on the Use of 0.7-in Diameter Strands in Precast Pretensioned Girders is supplemental to NCHRP Research Report 994: Use of 0.7-in. Diameter Strands in Precast Pretensioned Girders. The full text is available for download from the Transportation Research Board at https://www.trb.org/Main/Blurbs/182754.aspx