Print Email Facebook Twitter Physical, chemical and mineralogical characterization of Dutch fine recycled concrete aggregates Title Physical, chemical and mineralogical characterization of Dutch fine recycled concrete aggregates: A comparative study Author Nedeljković, Marija (TU Delft Materials and Environment; TNO) Visser, Jeanette (TNO) Nijland, Timo G. (TNO) Valcke, Siska (TNO) Schlangen, E. (TU Delft Materials and Environment) Date 2021 Abstract In circular concrete design, beside cement replacement with more environmentally friendly cement types, there is also an urgent need for sand replacement with fine recycled concrete aggregates (fRCA). The variations in physical and chemical properties of fRCA and lack of standards for their quality evaluation are the main reasons for not yet using fRCA in new concrete. In this study, an in-depth characterization of different Dutch fRCA is performed in order to examine suitability of fRCA as an alternative material for river sand and define indicators for fRCA quality. These indicators eventually can be related to concrete mix design and performance, so that fRCA can be classified as a material that can be used in structural concrete elements. This is achieved with physical, chemical and mineralogical characterization of individual and total fractions (0–0.250 mm, 0.250–4 mm and 0–4 mm). The physical properties such as grading, density, surface area, water absorption and cement paste content of fRCA were tested. The chemical analyses include quantification of element composition with X-ray fluorescence spectrometry (XRF) and carbonate content with thermogravimetry and mass spectrometry (TG-MS). Potential contamination (chlorides and sulfates) and reactivity of selected fractions were evaluated. In addition, qualitative and quantitative phase analyses with X-ray diffraction (XRD) combined with Rietveld refinement method were performed and supported by optical polarizing-and-fluorescence microscopic (PFM) study. Based on combined experimental approaches, characteristic quality indicators were defined for fRCA. These indicators showed that fRCA were uncontaminated and nonreactive. Despite fRCA were from different origins, they had similar chemical and mineralogical composition and contained comparative chloride content. In contrast, the content and surface area of fine fraction (0–0.250 mm) and particle size distribution of fRCA varied with the source. With this it can be assumed that fRCA will have different effect on the properties of the new concrete. Subject Circular concreteFine recycled concrete aggregatesMicroscopic studyMineralogyQuality indicators To reference this document use: http://resolver.tudelft.nl/uuid:0c686221-a2b7-4a07-b469-fc5534b4af17 DOI https://doi.org/10.1016/j.conbuildmat.2020.121475 ISSN 0950-0618 Source Construction and Building Materials, 270, 1-20 Part of collection Institutional Repository Document type journal article Rights © 2021 Marija Nedeljković, Jeanette Visser, Timo G. Nijland, Siska Valcke, E. Schlangen Files PDF 1_s2.0_S0950061820334796_main.pdf 9.29 MB Close viewer /islandora/object/uuid:0c686221-a2b7-4a07-b469-fc5534b4af17/datastream/OBJ/view