Propiedades mecánicas del hormigón reciclado con residuos de la construcción y demolición

Abstract

The use of construction and demolition waste (CDW) in the concrete manufacture allows to include the concept of sustainability in the construction industry; widely seen as one of the sectors with the greater negative impact on the environment, due both its elevated generation of waste and its high consumption of natural resources. In order to offer a possible solution to the environmental problem through the reuse of this type of waste, the research work first tested the suitability of construction and demolition waste as coarse aggregate according to the Code on Structural Concrete (EHE-08), and subsequently evaluated the effect of a partial replacement (50%) of conventional coarse aggregate (gravel) with CDW recycled aggregate on the mechanical properties (modulus of elasticity, compressive strength, tensile splitting strength and flexural strength) of a 25 MPa concrete mix. The recycled aggregates characterization carried out shows that the sample is suitable for use in concrete as coarse aggregate, as it meets the requirements of granulometry, particle size, density and shape; and the lack of compliance within the quality of fines and water absorption requirements could be rectified by subjecting the aggregates to a treatment of screening and water saturation prior to their use in the concrete manufacture. However, the value of resistance to fragmentation limits their application to concrete mixes with characteristic compressive strength below 30 MPa. Regarding the results of the mechanical tests performed on the hardened concrete, the values obtained suggest that it is feasible the use of recycled aggregates from construction and demolition waste in concrete manufacture without this being a loss of the mechanical characteristics. Thus, this reutilization alternative of construction and demolition waste comes as an environmental relief as it reduces the landfill of inert wastes easily usable as secondary building materials while prevents the extraction of further natural resources. Moreover, ...