Mechanical and chloride permeability properties of coarse fibre reinforced concrete

Synthetic fibers have been widely studied as reinforcing materials to increase the mechanical and durability properties of concrete. According to its diameter, fibers can be categorized as micro and macro (or coarse) fibers. As most research focuses on the mechanical properties of fiber reinforced concrete, its chloride permeability properties have been rarely studied. In this investigation, the compressive strength, flexural strength and chloride permeability of concrete with steel fibers (SF) and two types of coarse synthetic fibers, polypropylene (PP) fibers and polyvinyl alcohol (PVA) fibers were studied. It was found that steel fibers are able to improve both the compressive strength and the flexural strength of concrete. Addition of PP and PVA fibers could improve the flexible strength of concrete, with little effect on the compressive strength. Furthermore, test results show that addition of PP fibers slightly increases the chloride permeability of concrete while PVA fibers slightly reduce the chloride permeability