Latex-modified fiber-reinforced concrete bridge deck overlay : construction/interim report.

PDFTech ReportExperimental Features Project No. OR 90-01Latex modified concreteFiber reinforced concreteBridge decksOverlays (Pavements)LatexPortland cement concreteAdmixturesCrackingDebondingSteel fibersOregonOregon. Dept. of Transportation. Research UnitHouser, Elizabeth A.James, Charles P.Oregon. Dept. of Transportation. Research UnitOregon. Dept. of TransportationUnited States. Federal Highway AdministrationUS Transportation CollectionLatex-modified concrete (LMC) is Portland cement concrete (PCC) with an admixture of latex. LMC is considered to be nearly impermeable to chlorides and is extensively used to construct bridge deck overlays. Unfortunately, some of these overlays have developed permature cracking and debonding. In an effort to deter these problems, steel fibers have been added to LMC to create LMFRC.Construction problems included insufficient quality control, quick-setting, poor workability of the mix, extra time taken to add materials on site, tearing of the latex mat during finishing and tining difficulties caused by snagging the fibers. Clumping of fibers is a problem reported in other studies. All in-situ strength test results were below the typical strength range of LMC samples. Preparation of the deck for resurfacing should cost the same for LMC and LMFRC but materials and labor are generally higher for LMFRC.Two years after construction, the overlay had good bonding and no visible cracks. As compared to LMC overlays, LMFRC overlays are generally more difficult to construct and required more time, labor, and money