Thermische Leitfähigkeit von Stahlfaserbeton - eine theoretische Betrachtung

Thermal conductivity of steel fibre reinforced - a theoretical view

With respect to fire design of reinforced and prestressed concrete structures the thermal conductivity λc is one of the important input variables. In case of an addition of steel fibres, statements are contradictory about how these affect the thermal conductivity, and thus, the fire resistance. Against this background, literature data was sighted and completed by systematically theoretical considerations and an computer-based evaluation method. On the basis of theoretical considerations for the thermal resistance of concrete, as well as on the numeric model, in general it can be concluded that, for an in practice frequently used fibre dosage of 1 Vol.-%, the lower and upper curves for the thermal conductivity given in DIN EN 1992-1-2:2010 can be applied for normal- and high-strength concretes. However, for other types of concrete which specifically differ from normal- and high-strength concrete in density, kind, size and distribution of pores as well as in physical and chemical water binding capacity separate observations should be made.