Investigation on the Limitations of Accelerated Migration Test Applied to UHPFRC with Steel Fibers

Abstract

Ultrahigh-performance fiber-reinforced concrete (UHPFRC) is endowed with outstanding durability. The first results of accelerated migration tests with an adapted procedure highlighted a very low chloride permeability profiles for undamaged UHPFRC with organic and metallic fibers. However, some of the samples with steel fibers showed useless results in the accelerated migration tests because they presented signs of corrosion and cracks. This paper proposes to analyze by imaging the UHPFRC with steel fibers after the accelerated migration tests to better understand why some samples do not successfully pass the test. Image analyses were applied to characterize the distribution of the fibers, in terms of volume, homogeneity, and orientation. The results presents some correlation between those parameters and define some limitations on the type of UHPFRC that can be successfully characterized with accelerated migration test.