Mechanical properties of ultra high performance concrete reinforced by polypropylene fibers and synthetic macro fibers (barchip)

The use of concrete with ultra high performance reinforced steel fiber has been investigated in numerous studies. However, most research has focused on the use of steel fibers as reinforced. In this study, the replacement of steel fibers with polypropylene fibers and synthetic fibers (barchip) was investigated in the parameters of the mechanical properties of this concrete. The same use was also made of two hybrid fibers, as well as hybrid with steel fibers has been investigated. The total fiber content in each mixing plan is considered to be 1.5% vol. A total of 28 specimens 70x70mm cubes and 14, 100x200mm cylindrical specimens were made for compressive strength testing and 28 specimens of 70x70x 350mm were used to test the flexural strength. The compressive and flexural strength tests were measured at 7 and 28 days. the compressive strength of samples made at 28 days of age at all levels of the fibers used was more than 100 MPa ., the highest rupture stress relates to 28-day steel fiber reinforced specimens of 23.9 MPa.