Objective 2
Physical and mechanical behaviour of concrete with recycled fibers
Investigating the possible contribution of recycled fibers, even in combination with recycled aggregates, is one of the three main tasks of the EnCoRe Project. The material behaviour at both fresh and hardened state will be investigated. With reference to the former, the effectiveness of current mix-design approaches to achieve a target fresh state performance will be investigated. This will include also a multiscale characterisation (e.g. cement paste, mortar, and fiber reinforced composite) of the fundamental rheological properties. As for the latter, investigation will include also non conventional properties and requisites which may be due right to the use of non conventional fibers and aggregates, such as, e.g., fibers and rubber particles from tires, which may impart to the composite superior impact resistance and resilience.
The main goals of the activities planned within the Objective 2 of the research proposal are shortlisted below:
- investigating the behaviour of concrete reinforced with fibers obtained by plastic wastes (i.e., PVC, PET, and so on so forth), and possibly realised with RCA;
- investigating the behaviour FRC with steel fibers obtained by recycling the reinforcement of rubber-tyres;
- investigating the possible effect of rubber particles as aggregates on the toughness of the above mentioned fiber-reinforced concretes;
- investigating the behaviour of RSFRC realised with RCA.
Both experimental and theoretical/numerical modelling activities will be carried out to the aforementioned goals. The former will provide new results about the innovative materials at issue, whereas the latter will be used for extrapolating to the structural scale the findings of the experimental tests of small samples. Moreover, the theoretical-computational researches will evaluate failure behaviour of these innovative materials at both macro and mesoscopic level of observations. This will allow obtaining a deeper knowledge on the interactions among fibers, aggregates, mortar and rubber materials as well as the influence of their respective characteristic lengths on the overall response behaviour in pre- and post-peak regimes.