Hybrid industrial/recycled SFRC: Experimental analysis and design

This paper is intended as a practice-oriented contribution about the use of sustainable Fiber-Reinforced Concrete (FRC) in the design of structural members according to the provisions of the current codes and guidelines. More specifically, the work focusses on Hybrid Industrial/Recycled Steel Fiber-Reinforced Concrete (HIRSFRC) realised by combining tailored Industrial Steel Fibers (ISFs) with Recycled Steel Fibers (RSFs), the latter being obtained by recycling waste pneumatic tyres. First, the results of a series of experimental tests, carried out for characterising the behaviour of the aforementioned materials, are summarised. They are specifically considered for evaluating the parameters that are generally considered for describing the post-cracking response of FRC. Then, a parametric analysis on the sectional behaviour of beams made of the aforementioned HIRSFRCs is proposed: this is intended at highlighting the influence of the material behaviour on the ultimate bending moment and curvature of structural members.