The design, fabrication, and load-testing procedures are described for girders composed entirely of glass-reinforced polyester (GRP) resin. The girders are 4.9 m (16 ft.) long and have geometric features which include trussed webs, a solid flange plate, and a triangular-shaped cross section. Three of the girders were attached laterally by a GRP cover plate in the laboratory to provide a complete superstructure for a pedestrian bridge 4.9 x 2.1 m (16 x 7 ft.). The lightweight, high strength, and formability of the GRP materials permitted fabrication and handling of both the components and the completely assembled structure without the use of heavy equipment. The weight of the GRP superstructure was approximately 360 kg (800 lb.). Laboratory tests were conducted to ascertain the load transfer characteristics at the GRP plate and concrete deck interface. Live load tests were performed to measure strains, deflections, and the creep behavior of a full-scale girder exposed to prevailing climactic conditions. Comparisons of theoretical and experimental results ranged from nearly zero up to 20% in which the experimental results were usually lower than the predicted values for deflections and strains. The bridge is scheduled for field erection in 1978 and observations will be made for five years to monitor its structural behavior, the effects of weathering, and user abuse./Author/