ABSTRACT
This chapter reports a study carried out in order to: (i) evaluate the impact of the utilization of recycled concrete aggregates on the flexural behavior of reinforced concrete beams and (ii) assess the applicability of the Eurocode 2 to estimate the parameters characterizing the mentioned behavior. Four-point bending tests were performed on beams manufactured with four different concrete mixes. Three of them contained recycled aggregates while the fourth one was a reference containing only natural aggregates. The different mechanical properties of concrete and steel used to manufacture the beams were measured through standard tests. Deflection, crack spacing and crack width along the beams as well as loading force and displacement were monitored during the bending tests. The recorded parameters were compared to the values determined using the Eurocode 2 prescriptions. An impact of the use of recycled aggregates was detected on all the serviceability-limit-state parameters that were investigated. The Eurocode 2 specifications gave quite accurate estimations of the experimental deflections, independently of the recycled aggregate content, provided that the actual mechanical properties of the materials are used as inputs. As for the cracking parameters, the Eurocode 2 expressions seem to overestimate the actual measured values on the beams containing recycled aggregates. A theoretical analysis of the Eurocode 2 cracking model is made so as to explain this discrepancy. Finally, no noticeable effect of the incorporation of recycled aggregates on the flexural strength and the failure mode of the beams was demonstrated. Accordingly, the Eurocode 2 approach applies well in order to estimate the failure parameters of recycled aggregate concrete beams tested in this work.
