Behavior of Standard AASHTO Type I Pretensioned High Performance Lightweight Concrete Beams with Fully Bonded ½-Inch Prestressing Strand

High performance lightweight concrete is desirable for use in Texas bridge girders to bring about significant reductions in the dead load of the structure. Concrete can be specified to have a unit weight of less than 120 lb/ft3 (18.9 kN/m3) with compressive strengths of 6000-8000 psi (41.4-55.2 MPa). Full-scale beam specimens were tested in order to determine the feasibility of their application in the field. The development length of the ½ in (12.7 mm) prestressing strands was measured, and an upper bound of 60 in (1524 mm) was determined. This indicated that the AASHTO specifications are conservative for both normal weight and lightweight concrete. The flexural behavior of the lightweight beams was similar to the behavior of the normal weight beam.