The Use of Pelletized Concrete as Coarse Aggregate in Precast Industry: Technology and Mechanical Properties

To promote Circular Economy in the construction industry, it is fundamental to reuse waste material as partial replacement of the natural one, reducing the environmental impact of manufacturing processes. The efficient and circular use of materials can be effectively applied to the production of concrete and to the precast industry. To this purpose, Truzzi S.p.A. decided to tackle the problem of the management of residual concrete from the production of precast structural elements. In this framework, a pelletizing agent recently developed by Mapei S.p.A., which transforms the fluid mix into a granular material, has been tested. This paper shows how it can be used in the precast sector. The optimization of the recovery process drove to the generation of “granulato” which is made of natural coarse aggregate covered by a composite layer. “Granulato” has been subsequently used as coarse aggregate, completely substituting the natural one, to produce new concrete. Fresh and hardened concrete properties have been measured and analysed.