Comparison of Performances of Structural Fibers and Development of a Specification for Using Structural Fibers in Thin Concrete OverlaysStatus: CompleteReport Date: 09/24/2018 Summary: Researchers demonstrated through lab testing that synthetic fibers in thin concrete overlays keep cracks tight and help transfer loads across slabs. Fibers with irregular cross sections and high lateral stiffness perform well in overlays. While increasing dosage levels up to 1 percent fiber volume fraction of concrete mixture improves load transfer across cracks and seams, using fiber dosage levels that exceed 1 percent fiber volume fraction renders mixtures largely unworkable. Researchers provide recommendations for selecting fiber types and dosages in pavement design, and suggest a test for trial batches. Final Deliverables: Comparison of Performances of Structural Fibers and Development of a Specification for Using Them in Thin Concrete Overlays (Report #2018-29) Selecting Structural Synthetic Fibers for Use in Thick Concrete Overlays (Research Summary) Related Materials: Structural fiber choice for thin concrete pavements can have a significant impact on quality (News/Publication Article) Selecting Structural Synthetic Fibers for Use in Thin Concrete Overlays (Blog Post) Related Research: Development of an Improved Design Procedure for Unbonded Concrete Overlays Project Personnel: Principal Investigator: Manik Barman Technical Liaison: Maria Masten Project Coordinator: Debra Fick Panel Members: Bernard Izevbekhai - Materials & Road Research Cory Slagle - Washington County Transp Division Dave Fennessy - BASF Corporation Greg Halverson - Brock White Lowell Flaten - District 8 Mark Johnson - BASF Matt Zeller - CPAM (Concrete Contractors) Robert Golish - Materials & Road Research Rodrick Garver - Soils and Materials Thomas Burnham - Materials & Road Research Timothy Andersen - Materials & Road Research Todd Howard - Dakota County
