Influence of length and dosage of polypropylene fibres on the spalling tendency and the residual properties of self-compacting concrete after heated at elevated temperatures

The objective of this paper was to study the influence of different length and dosage of polypropylene fibres on the properties of self-compacting concretes at elevated temperatures. A total of five self compacting concretes and one normally vibrated concrete were produced. The poypropylene fibres were of different length (12 mm, 6 mm and 3 mm) and were added at dosages of 1.0 Kg/m3 and 0.5 Kg/m3. The properties measured after fire exposure were the compressive strength, splitting tensile strength and water capillary absorption. The best overall performance was observed on the fibre reinforced self compacting concrete produced with the 6 mm HPR fibres at a dosage of 0.5 Kg/m3