In einem Forschungsprojekt des Labors für Baustofftechnik der TH Köln wurde der betontechnologische Einfluss von Mikro- und Makrofasern aus Polypropylen auf die Wiederverwertbarkeit (Recyclingfähigkeit) damit hergestellter Betone untersucht. Der Beitrag geht der Frage nach, inwieweit sich wesentliche Frisch- und Festbetoneigenschaften infolge von PP-Fasern im Betonbruch (Typ 1) bei der Verwendung als Gesteinskörnung verändern, und stellt Möglichkeiten zur Separation von Makrofasern aus Betonbruch von PP-Faserbetonen dar.
Recyclability of concrete with PP fibres
A research project conducted by the Laboratory for Building Materials Technology at Technical University of Cologne investigated the influence of polypropylene microfibres and macrofibres on the recyclability of concrete produced using these fibres. The contribution examines the extent to which essential fresh and hardened concrete properties change as a result of PP fibres in crushed concrete (type 1) when used as aggregate, and presents possibilities for separating macrofibres from crushed concrete from PP fibre concretes. The research project has shown that both microfibres and macrofibres in recycled aggregate from PP fibre concrete have no significant influence on the essential fresh and hardened concrete properties of concrete whose aggregate consists of 25 % by volume of this recycled material. No negative effects of PP fibres in the recycled aggregate (when added in a classified manner) were observed in terms of uniformity either. If the aim is to separate macrofibres from the concrete rubble of PP fibre concretes, this can be achieved using conventional processing and sorting technology after the usual preliminary tests to determine the process parameters (including the degree of comminution of the concrete rubble and suitable separation/sorting parameters, e.g. air velocity in a wind classifier).