• Compared to what is typically observed for normal concrete and HPC, variation in the reported UHPC properties is typically minimal provided sample preparation is done carefully.
• UHPC possesses many beneficial engineering properties over normal concrete and HPC. Although the UHPC has tensile strength as much as over four times the tensile strength of normal concrete and possesses some dependable inelastic tensile behavior, the tensile strength of UHPC is only a fraction of its compression strength, suggesting that these characteristics are still not conducive to develop optimal design solutions. However, this challenge can be easily overcome by utilizing a high amount of prestress, which is possible due to the high compressive strength of UHPC that is as high as five times the compressive strength of normal concrete. Since UHPC leads to thin members with reduced cross-sectional areas, inducing high amounts of prestress can be achieved effectively without needing an excessive amount of prestressing steel.
• Although it is not a critical requirement, thermal curing is ideal for UHPC, which requires subjecting UHPC members to 194°F over 48 hrs. This curing process can be achieved in a precast concrete plant and was used in applications where UHPC members were prefabricated. Most of the 450 x 10-6 shrinkage strain occurs during thermal curing of the UHPC members. After curing, the UHPC members are expected to undergo almost no further shrinkage.
• The enhanced durability properties of UHPC when compared with those of normal concrete and HPC are important driving factors for the application of UHPC. The durability characteristics of UHPC, particularly its excellent resistance to chloride ion penetration due to its low capillary porosity, make it extremely resistant to corrosion, even with the inclusion of a large proportion of steel fibers in the UHPC mixture.

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