Strain capacity and flexural strength behavior of bendable concrete produced with different polymeric fibers

Abstract

The incorporation of fibers into engineered cementitious composite concrete imparts flexibility to the material. Therefore, using different types and contents of polymeric fibers would affect the behavior of such concrete types, and it is worth contemplating. The present research aims to study the flexural strength and the strain capacity of engineered cementitious composite concrete produced with polyvinyl alcohol fibers (PVA) and polypropylene fibers (PP) with different volume fractions (1%, 1.5%, and 2%). Six mixes of engineered cementitious composite concrete of three grades of strengths, 30, 45, and 60 MPa, were produced. Results revealed that mixes of 60 MPa with 2% PVA fibers recorded the highest strain capacity, which reached (17.6%) compared to mixes of 60 MPa with 2% PP fibers. The maximum enhancement in the flexural strength was (4.3%),(6%), and (23%) for mixes of 30 MPa, 45 MPa and 60 MPa. This enhancement may open the horizon for using high-strength engineered cementitious composite concrete reinforced with PVA fibers in structural applications exposed to flexural strength, providing a lighter weight due to the exclusion of bar reinforcement. Also, its high strain capacity reduces the tendency for microcracks formation. The standard deviation error bars for the average flexural strengths of bendable concrete mixes with different fiber contents and types show no differences when comparing the same strength and fiber types. For example, mixes of 60 MPa with PVA fibers give less than 2 MPa standard deviation when compared for different fiber volume fractions.

Keywords

• bendable concrete
• mechanical properties
• polypropylene fibers
• polyvinyl alcohol fibers
• strain capacity