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An assessment of the carbon footprint of concrete mixtures in relation to early strength development, evaluated using various maturity models

Solomon Addisu, Ratajczak Maria

Advances in Science and Technology. Research Journal

2025

Vol. 19, no. 4

171--182

This research aims to establish robust strength-maturity correlations for concrete produced using various cement binders, along with a comprehensive assessment of the carbon footprint of ready-mix concretes manufactured with each cement type. The study employs two maturity calculation methods: the Time-Temperature Factor (TTF) approach and the weighted maturity method, to evaluate early strength development. Six cement binders were tested, including CEM I 42.5R, CEM V/A (S-V) 32.5R-LH, and various CEM II variants. The heat of hydration for each binder was measured, and the development of mechanical properties was monitored through temperature measurements and compressive strength tests. Additionally, a carbon footprint analysis was conducted to evaluate the environmental impact of the ready-mix concrete in relation to its early strength development. The results confirm significant variations in strength development, with rapid growth observed in concretes containing CEM 42.5 classes, whereas slower strength gain was noted in concretes manufactured with CEM II/B-M (V-LL) 32.5R and CEM V/A 32.5R-LH. At the same time, binders with slower early strength development are characterized by a significantly lower carbon footprint, contributing to the positive environmental impacts of the investigated mixtures produced with low-emission binders. These findings underscore the challenges of balancing the use of low-emission binders with the construction industry's demand for accelerated processes.

The effect of recycled aggregates on the accuracy of the maturity method on vibrated and self-compacting concretes

Velay-Lizancos M., Martinez-Lage I., Vazquez-Burgo P.

Archives of Civil and Mechanical Engineering

2019

Vol. 19, no. 2

311--321

Fine and coarse recycled aggregate used jointly as partial replacement of natural aggregate is not allowed for structural concrete in many international standards. More studies about it are needed toward more ecofriendly standards. This research studies one important aspect for structural concrete: the influence of recycled aggregate on the accuracy of the maturity method. A total of 7 mixes were studied with two types of reference concretes: vibrated (VC) and self-compacting concrete (SSC). For vibrated concrete, we studied 4 mixes with different partial replacements of recycled aggregates: 0%, 8%, 20% and 31%. For self-compacting concrete, the partial replacements were 0%, 20% and 50% of the total amount of aggregates. We found that, for percentages equal or higher than 20%, the higher is the percentage of recycled aggregate, the higher the activation energy. It was observed that a unique curve “Maturity–Relative strength (S/S∞)” can be used for each type of concrete (SSC or VC) independent of the percentage of recycled aggregate. In addition, we found higher accuracy of the estimations using the hyperbolic equation for the curve “Maturity–S/S∞” than using the exponential equation; applying the hyperbolic approach, less than 3% of the estimations had an error higher than 10%.