Influence of polyvinyl alcohol, steel and hybrid fibers on fresh and rheological properties of self-consolidating concrete

Fiber-reinforced self-consolidating concrete (FRSCC) has a tremendous potential to be used in construction industry because it combines the advantages of both self-consolidating concrete (SCC) and fiber-reinforced concrete (FRC). Nineteen concrete mixtures are developed by incorporating different dosages (up to 0.5% volume or 22  kg/m322  kg/m3 of concrete) of polyvinyl alcohol (PVA) and metallic fibers and their combinations. The influences of fiber types, size, dosages, and fiber combinations (used in hybrid mixes) on fresh (slump flow, L-box passing ability, V-funnel flow time, and segregation index—a measure of workability) and rheological (viscosity and yield stress at various time intervals ranging from 10 to 70 min) properties are critically analyzed on the basis of experimental results. The workability/rheological properties of concrete mixtures are found to depend on types, dosages, geometry of fiber, and in cases of hybrid mixtures, interaction and synergic properties between different fiber types also play a critical role. The maximum dosage of PVA is limited to 0.125% compared with 0.3% of metallic fibers in developed FRSCC mixtures because of PVA’s higher workability reduction/viscosity increase capability. In addition, relationships among fresh/workability and rheological properties are also established.