Abstract
Over the next several years, new mixtures for ultra high performance concrete (UHPC) products are expected to move from prepackaged mixtures toward the use of locally available materials to make UHPC economically viable for future projects. Because a wider variety of materials will be used in UHPC, it will be necessary to develop or modify material specifications to ensure high quality UHPC mixtures are produced that provide strength and durability properties consistent with designers’ expectations. New or modified specifications will be needed for chemical requirements on the cement and supplementary cementitious materials considered for use in UHPC as well as to guide producers in the selection of aggregates for use in UHPC. This paper discusses these material issues along with issues related to admixture and fiber selection that are important to the future development of UHPC. Suggestions for development or modification of specifications that will ensure selection of high quality materials and potential performance based specifications that may evolve in the future are also provided.