This study is concerned with the possibility of utilizing fiber reinforced plastic rods as prestressing tendons, in place of traditional steel tendons, in elements of prestressed concrete bridges exposed to corrosive environments.
A survey was made of available information on the behavior characteristics of fiber reinforced plastic tension elements, and in particular those of glass fiber reinforced (GFR) tension elements. Also, an analytical study was made of the flexural behavior of concrete elements prestressed by GFR tendons.
Based on the analytical study and on the survey of available information, an assessment is made of the impact on the design of prestressed concrete members if GFR tendons are used. Some preliminary design recommendations are made, together with proposals for research needed before GFR prestessing tendons should be used in practice.
Four GFR tendons with Con-Tech Systems anchorages were tested, the primary variable being the embedded length of the GFR rods in the anchorages. All the tendons failed by the rods pulling out of the anchorages. For embedded lengths of 385 mm (15.2 in) or greater, the failure loads were about 90 percent of the advertised tendon strength of 220 ksi, or about 100 percent of the guaranteed tensile strength of 197 ksi (60 kN/rod).