Materiales de Construcción, Vol 70, No 339 (2020)

Microstructural analysis of concretes manufactured with recycled coarse aggregates pre-soaked using different methods

Z. Sánchez-Roldán
Department of Building Construction, ETS de Ingeniería de Edificación, University of Granada, Spain

I. Valverde-Palacios
Department of Building Construction, ETS de Ingeniería de Edificación, University of Granada, Spain

I. Valverde-Espinosa
Department of Building Construction, ETS de Ingeniería de Edificación, University of Granada, Spain

M. Martín-Morales
Department of Building Construction, ETS de Ingeniería de Edificación, University of Granada, Spain


Recycled concrete has a microstructure more complex than natural concrete, as it includes new interfacial transition zones, the quality of which is conditioned by the state of humidity of the aggregates used, which in turn will affect the final properties of the concrete. Bearing in mind the greater absorption capacity of recycled aggregates, it is important to improve its properties by means of a treatment method that is capable of reducing the negative effects that this may produce in the new concrete. Therefore, the influence of the pre-soaking method of recycled aggregates on the formation of the microstructure of concretes manufactured with these aggregates is analysed, to determine which treatment is the most effective for the production of concretes for non-structural use. The results show that the microstructure of the evaluated concretes differs according to the treatment method used, the most optimal method being one that uses aggregates without pre-soaking.


Concrete; Interstitial Zone; Waste treatment; Microstructure; Image analysis

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