Feasibility Study of Development of UHPC for Highway Bridge Applications in Nebraska

Ultra-high performance concrete (UHPC) is a new class of concrete that has mechanical and durability properties that far exceed those of conventional concrete. The use of UHPC will result in significant improvements in the structural capacity and durability of bridge components. As a result, issues such as cracking and leakage in bridge wet joints can be largely eliminated. However, because of the highly sophisticated mixture design and raw material availability, the current use of UHPC in the United States (U.S.) is limited to proprietary pre-packed products provided by international suppliers. The high material cost associated with these products, which can be as high as $2,000 per cubic yard in additional to batching, placing, and curing costs, has greatly prevented the wide use of UHPC in bridge applications. Therefore, there is an urgent need to develop economical non-proprietary UHPC mix(es) with materials readily available in Nebraska. The research team at the University of Nebraska-Lincoln (UNL) has successfully completed a research project in 2009 on the development of 15-20 ksi High Performance Self-Consolidating Concrete (HPSCC) with locally available materials. However, there is no comprehensive study of the durability of the developed mixes to ensure the success use of the material in highway bridge construction. Also, there is a need to further improve the mechanical and visco-elastic properties of these mixes through the incorporation of steel fibers and to optimize mixture design through the inclusion of new filler materials such as micro silica, and limestone powder.