Abstract

Fiber reinforced concrete is an improved type of concrete that containing fibers randomly distributed inside it. Usually, the mechanical properties of concrete have been developed namely, compressive, flexural, and tensile strength by adding the fibers. In addition, the fiber makes the concrete very durable, tougher and lower permeability. This paper aims to enhance the concrete mechanical properties by adding polypropylene fibers in combination with high performance cement as a partial cement replacement. The combination of both polypropylene fibers and high performance cement in concrete gave excellent values of flexural, tensile and compressive strength. Seven percentages of polypropylene fibers were used while two percentages of high performance cement were used, in addition to normal specimens of concrete without any admixtures. Test results give a well improvement by using both polypropylene fibers and high performance cement. The flexural strength and the tensile strength are increased significantly from 2.7 to 14.5 MPa, and from 1.9 to 7 MPa, respectively. While concrete strength of compression increased from 30.1 MPa to 42.9 MPa due to inclusion of polypropylene fibers and high performance cement. The concrete specimens with including both high performance cement and polypropylene fibers had adequate strength to counteract further cycles of loading after releasing 1st failure load.