Compressive Strength and Rapid Chloride Permeability Testing of Concrete Comprising Silica Fume

The objective of this research was to evaluate the effects of currently available sources of silica fume on the compressive strength and chloride permeability of concrete mixtures proportioned to be similar to that used in the decommissioned Salt Lake City Airport parking garage. The procedures for this research involved mixture design and materials acquisition, batching of four concrete mixtures, measuring properties of the fresh concrete, casting and curing of concrete specimens, and measuring properties of the cured specimens. Regarding strength, the results indicate that, at 7 days and 28 days, the compressive strengths of concrete mixtures comprising silica fume were 29% to 52% higher and 12% to 28% higher, respectively, than those of the control mixture without silica fume. Regarding chloride permeability, the numbers of coulombs passed by concrete mixtures comprising silica fume were 55% to 74% lower than that of the control mixture. These results demonstrate the benefits of concrete comprising silica fume for future projects, where maximizing the service life of concrete structures is important.