Suchergebnisse

This study presents a novel methodology to evaluate the self-healing capability of Ultra High-Performance Fiber-Reinforced Concrete (UHPFRC) designed to compare conventional concrete types. The procedure used combines loading reinforced concrete elements until a fixed strain level to have a comparable total crack opening. Afterwards, water penetration to chlorides is used as an indicator of permeability. This work compares autogenous healing efficiency of a conventional concrete, a high-performance concrete, and two types of UHPFRCs with and without 0.8% of a crystalline admixture (CA) by the binder weight. The results show that all UHPFRC specimens exhibited excellent autogenous healing, higher than conventional concretes for an equivalent total crack. The self-healing results depended greatly on the crack size and the fiber content. Additionally, UHPFRCs with CA obtained the lowest water permeability after promoting self-healing for one month in water immersion and presented almost complete healing against chloride penetration. ; The activity described in this paper has been performed in the framework of the project "Rethinking coastal defence and Green-energy Service infrastructures through enHancEd-durAbiLity high-performance cement-based materials-ReSHEALience", funded by the European Union Horizon 2020 research and innovation programme under GA No 760824. The authors would also like to thank Sika and Penetron for providing materials for the tests and E.J. Mezquida-Alcaraz for the characterization of UHPFRC mixes with Inverse Analysis.