Rapid migration chloride test for Ultra High Performance Fiber Reinforced Concrete

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North American civil infrastructure systems, such as, roads, bridges, overpasses, marine and airport facilities, are facing premature concrete deterioration due to the severe climatic conditions and chemical attacks. In this context, new cement based materials Ultra High Performance Fiber Reinforced Concrete (UHPFRC) have been emerging for their outstanding ductility and durability properties in infrastructure applications. UHPFRC is a new class of cement-based composites with a highly compact cementitious matrix reinforced by an optimal system of fibers. UHPFRC are endowed with outstanding mechanical properties in terms of ductility and toughness. As a consequence, UHPFRC are highly resistant to durability issues, such as, freeze and thaw and salt scaling as proven by laboratory tests. The use of UHPFRC can effectively imply material saving, but also guarantee a structure lifetime of a century under the most severe environmental marine environment. However, the current accelerated tests for characterizing the penetration rate of chloride in concrete do not apply for UHPFRC due to the dense matrix. There is today a critical need to provide meaningful chloride diffusion coefficients for predicting the life time of UHPFRC structures. The research objective is fourfold: (1) To develop an accelerated migration test which is suitable for characterizing the chloride migration for UHPFRC; (2) To study the effect on chloride transport for two fiber kinds and level of microcracking; (3) To study the effect of chloride on the creep properties of UHPFRC; (4) to compare the results with real marine environmental conditions for a general comprehension. Providing a scientific approach to evaluate the lifetime of UHPFRC will help decision makers to invest in more durable solutions for our infrastructures.