The research has led to the development of high thermal conductivity screeds, able to optimize the performance of underfloor heating systems. The increased thermal conductivity fosters the heat transfer from screed to internal environment in terms of temperature distribution and heat flow effectively released. Then it guarantees an improved system efficiency in terms of in consumptions reduction, if evaluated at the same temperature set point. The developed products were obtained starting from a standard concrete mixture (UNI EN 196-1), with the addition of different kinds of high conductivity fibres, differentiated by type of material, particle size (average size of the single fibre diameter and length) and amount of matter added. The research activities has determined the optimum trade-off between provided thermal performance and costs of production (cost/benefit analysis).
Concrete mixture specimen with the addition of copper fibre
The insertion of high conductivity metal fibres into the concrete screed and the study of morphology and size of introduced particles, allows a high increase of thermal conductivity to values unreachable by standard concrete mixtures, ensuring an optimized distribution of surfaces temperatures. The experimental analysis and the numerical simulation of their thermal performance has allowed the estimation of a linear trend. With this trend is possible to evaluate the thermal performance also for screed, which contain copper as a percentage not taken into consideration by experimental analysis.
The product is potentially usable into high performance underfloor heating system. The possibility of change the product's different technical parameters (type of added material, morphology and fibre's amount, screed's thickness) allows to create an adaptable product for different kinds of stratigraphy, system requirements or climatic zones.
Concrete mixture for evaluate the contribution of copper fibre in the product's thermal performance.
Underfloor heating systems and all situations where is needed high thermal conductivity. For instance if it is needed high conductivity material for filling vertical geothermal probes with low enthalpy.
The use of screed with copper fibres as additive, checked the increased thermal conductivity, allows a better efficiency in the heat transfer from the underfloor to internal environment. The addition in the concrete mixture of long high conductivity fibres allows to achieve higher values of thermal conductivity both in absolute and tendency terms, come to image more increase of thermal conductivity compared to short fibre, with the same quantity of copper in addition. The highest percentage increase verified in terms of thermal conductivity is about 30%, compared to the screed without additives.
Green Steel Solana S.r.l., Oggiono LC Companies working in the area of premixed concrete
The variety of services and solution applicable to this kind of product is introducing into the area of the premixed concrete manufacturers.
Installation of screed on a floor heating system