ABANDON THE USUAL : ULTRA-HIGH-PERFORMANCE CONCRETE PROVES STRONGER - AND STRANGER - THAN THE CONVENTIONAL

Ultra high performance concrete (UHPC), already in use in highway and pedestrian bridges in Europe, Asia, and Australia, is now beginning to gain attention in the U.S. Known for its uniquely high compressive strengths, UHPC, which is a steel-fiber-reinforced, reactive-powder concrete, also has such impressive durability features such that it is immune to freeze-thaw damage and abrasion, is almost impermeable to chloride ion diffusion and carbonation penetration, and once thermally treated, it exhibits minimal creep or shrinkage. This article discusses the composition of UHPC, its characteristics, and strength properties. It also describes the construction of an optimized UHPC bridge test facility that has been built for experiments investigating the integrity of longitudinal connections, transverse load distribution, and overall behavior. Additional girders will be evaluated for flexural capacity, shear capacity, and strength and fatigue life of the longitudinal connection.