Ultra-high performance concrete (UHPC) is a new class of concrete that has superior performance characteristics compared to conventional concrete. Despite of its advantages, UHPC is not commonly used in the precast/prestressed concrete industry. The main impediments to the wide spread of UHPC are: 1) The high cost for proprietary mixes, 2) Absence of user-friendly mixing and quality control procedures, and 3) Lack of technology and experience required to produce UHPC. The objective of this research is to produce economic user-friendly mixes to be used in fabricating precast/prestressed bridge I-Girders. Targeted mixes were achieved by using supplementary cementitious materials, low water-to-powder ratios, and high range water reducing chemical admixtures. Developed mixes had a 24-hour minimum compressive strength of 69 MPa, 28-day compressive strength of 104 MPa, and a minimum spread diameter of 64 cm. Developed mixes were used in producing precast/prestressed girders with superior strength characteristics at Coreslab Omaha, Inc. The developed girder had superior shear and flexural strengths compared to similar tested girders fabricated with normal concrete mixes.
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