Abstract : The purpose of this study was to investigate the effect of fiber type and content on the mechanical properties of non-proprietary, cost-effective ultra-high-performance concrete (UHPC) mixtures using locally produced material in the state of Florida with crushed limestone fine aggregate. Ultra-fine recovery (UFR) material was used for the first time to improve the particle packing and density of the non-proprietary UHPC mixtures. The UHPC mixes were developed using particle packing analysis and then modified through small trial batches. Qualified mix designs were further evaluated through several different experimental tests, including bulk resistivity. Results showed that using steel fibers with 0.2 mm diameter and 13mm length led to better performance compared to longer metallic fibers and nonmetallic fibers, and less clumping and segregation issues were observed on samples containing these fibers (0.2 mm and 13 mm length). In conclusion, non-proprietary UHPC mix designs containing 2% steel fibers made by locally produced material in Florida, can obtain comparable performance to commercial versions of UHPC mixtures.
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