Caratterizzazione di due calcestruzzi UHPFRC commerciali: valutazione di proprietà meccaniche e di durabilità

This note presents the results of a research aimed at assessing and comparing the properties of two commercial Ultra-High-Performance Fiber Reinforced Concretes (UHPRFC) made with the same amount of steel fibers (2.5% vol.). Besides the basic properties at hardened state, such as compressive strength and elastic modulus, durability-related parameters are measured, such as electrical resistivity, resistance to carbonation and chloride penetration, water absorption rate and water absorption. Microstructure is also studied by means of optical and electron microscopy. The results show that, although fibers may locally increase the presence of interfacial voids in the cement paste and decrease the electrical resistivity of UHPFRC, both products exhibited an overall excellent behavior if compared to ordinary concrete.