Abstract
Using polypropylene fibers treated hydrophilically for cementitious components by extrusion moulding, it has been confirmed that flexural behaviors of these components are improved. This paper deals with geometrical effects of this fiber from the viewpoints of improving the flexural behaviors of cementitious components on the basis of two series of experiments. The following items are clarified; l) Regardless of the geometrical effects of fibers, first cracked flexural strength and effective water cement ratio had a unique linear relation. 2) First cracked flexural strength could be predicted in general by extruding pressure. This knowledge was utilizable in the quality control in manufacture. 3) The relation between first cracked flexural strength and surface dry density was represented as a unique curve for every kind of fibers.
