Some Characteristics of Polypropylene Fiber Reinforced Concrete

A wide experimental campaign was carried out on concretes with the addition of polypropylene fibers. This way it was possible to obtain useful information on the morphological structure, on the trend in time of compressive strength, splitting tensile strength and impact strength, and on the influence on these trends of freeze-thaw, the nature of the aggregates and fiber dossage. The main conclusions indicate that compressive and tensile splitting strength are maximum for the quantity of fiber in correspondence with which the bulk density of the mixture is the maximum, and that the presence of the tiber does not have particular influence on phenomena connected to freeze-thaw, while it is especially beneficial from the point of view of plastic shrinkage and impact strength. The latter point makes the employment of fibers especially advisable for concrete paved roads and for bridge slabs where the dynamic action of vehicles interacts immediately with the structure.