h i g h l i g h t sMechanical properties and durability indicators of SFRSCC and SCC were assessed. Self-compacting requisites were maintained, adding 60 kg/m 3 of steel fibers to SCC. Steel fibers contributed for the increase of post-cracking flexural resistance. The addition of steel fibers to SCC did not affect the durability indicators. a b s t r a c tDurability is one of the most important aspects of concrete due to its fundamental incidence on the serviceability working conditions of concrete structures. Research on the durability of steel fiber reinforced self-compacting concrete (SFRSCC) is still scarce, particularly in the aspects of corrosion resistance, which did not yet demonstrate clearly whether the corrosion of steel fibers may or may not lead to cracking and subsequent spalling of the surrounding concrete.For conventional concrete, without steel fibers, there are some widespread used durability indicators, which applicability to SFRSCC and its common values are practically unknown. For this purpose, an experimental work with SFRSCC and self-compacting concrete (SCC) specimens was carried out in order to characterize their mechanical properties and evaluate durability indicators.The results showed that the addition of steel fibers to SCC was very effective in terms of increasing the post-cracking flexural resistance and the energy absorption, and did not affect significantly the selfcompacting requisites and the durability indicators of SCC.

Fiber reinforced concrete structures are subjected to chloride and carbonation penetration that could initiate corrosion of steel fibers, with eventual pernicious consequences in terms of structural and durability performance. Cracks in concrete are known to hasten initiation of steel corrosion in reinforced concrete structures. The investigation of the impact of cracks on the corrosion initiation and the associated interfacial damage between concrete and steel fibers is important for understanding the mechanical behavior of steel fiber reinforced concrete. In the present work, with the aim of studying the corrosion action on the mechanical behavior of cracked Steel Fiber Reinforced Self-Compacting Concrete (SFRSCC), an experimental program was performed to characterize the corrosion of hooked-end steel fibers and to assess the fiber pullout behavior in cracked concrete, previously subject to the action of corrosion by exposure to aggressive chloride environment.

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Steel fibers resulting from the industry of tire recycling can be efficiently employed in concrete to improve its mechanical performance, such as post-cracking load bearing and energy absorption capacity. Under chloride attack, an important aspect of Recycled Steel Fiber Reinforced Concrete (RSFRC) durability is its corrosion resistance. However, the insufficient knowledge on this domain contributes for a conservative design philosophy, which can compromise the cost competitiveness of RSFRC and prevent its application in elements where this occurrence, even eventual, is not acceptable.In the present work, an experimental program was performed with the aim of assessing the corrosion susceptibility of RSFRC including the characterization of the micro-mechanical properties and the corrosion resistance of recycled steel fiber (RSF) by means of nano-indentation testing, electrochemical monitoring techniques and scanning electron microscopy (SEM) analysis. The influence of the small rubber debris attached to the RSF surface was also analyzed by using two distinct pre-treatment methods. The adhesive bond behavior between the RSF and the surrounding self-compacting concrete (SCC) matrix was analyzed by performing monotonic RSF pullout tests. Double edge wedge splitting (DEWS) tests were conducted for evaluating the corrosion effects onthe post-cracking response of RSFRC.

For structural elements exposed to chloride environments, an important aspect of Recycled Steel Fiber Reinforced Concrete (RSFRC) durability is the corrosion resistance. In the present work, an experimental program was carried out to evaluate the long-term effects of chloride attack on the post-cracking behavior of RSFRC by performing splitting tensile tests and round panel tests. Two RSFRC mixtures defined based on the packing density optimization were produced with a fiber content of 0.8% and 1% per volume of concrete. The influence of different periods of chloride immersion was investigated, as well as the influence of fiber dispersion at crack surfaces of the specimens. Additionally, a simplified prediction of the long-term chloride penetration depth into uncracked RSFRC under immersion aggressive chloride exposure conditions was estimated. The RSFRC revealed high susceptibility to surface corrosion under the chloride exposure conditions adopted. However, the post-cracking resistance of RSFRC was not significant affected. The addition of RSF had a negligible effect in the diffusion of chloride ions into concrete, and the critical chloride content was higher than that found in conventional reinforced concrete structures.