As part of a multistate research program on use of high-performance concrete (HPC) in highway bridges, a bridge originally designed as a three-span adjacent box girder bridge was converted to a single-span bridge by using 70-MPa HPC and 15-mm strands. As part of the research, a test beam was constructed and tested. Instruments placed in the beam before casting were used to measure transfer length, which was found to be approximately 1.22 m, larger than the 50-bar diameters usually used in the American Association of State Highway and Transportation Officials (AASHTO) Standard Specifications but consistent with recent studies. After the beam concrete reached the required compressive strength, it was tested to destruction. The beam was able to resist the required AASHTO ultimate moment without failure. It was found that the AASHTO cracking load was conservative for this beam, mostly because the measured modulus of rupture greatly exceeded the value assumed in the AASHTO specifications. The behavior of the beam was successfully predicted using a section analysis.

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