Investigation of Fiber-Reinforced Concrete for Use in Transportation Structures

Results are presented of a laboratory investigation to determine the properties of fiber-reinforced concretes (FRCs) with steel (hooked-end), polypropylene (monofilament and fibrillated), and the recently introduced polyolefin fibers (monofilament) for application in pavements and bridge deck overlays. Concrete properties in the unhardened and hardened states were evaluated and compared. Although the ultimate splitting tensile strength, compressive strength, and first-crack strength were higher in most of the FRCs, when strength values were adjusted for changes in air content, only a few batches had higher strengths. The addition of fibers resulted in great improvements in flexural toughness and impact resistance. Three FRC pavement overlays were applied in Virginia in 1995. The FRCs used in the projects were similar to those used in the laboratory investigation, with similar fiber volumes, types, and sizes. To implement the findings of the study successfully, the performance of the FRC pavement overlays is being monitored.