Long-life slab replacement concrete.

PDFTech ReportBDV25-977-01Concrete pavementsSlabsPavement crackingField testsLaboratory testsHeat of hydrationThermal stressesTemperatureMix designAccelerating agentsFloridaFlorida. Dept. of TransportationZayed, AblaRiding, KyleFerraro, Christopher C.Bien-Aime, AndreShanahan, NatalliaBuidens, DanielMeagher, ThomasTran, VictorHenika, Justin D.Paris, Jerry M.Tibbetts, Caitlin M.Watts, Benjamin E.University of South Florida. Dept. of Civil and Environmental EngineeringUS Transportation CollectionThis research was initiated following reports of high incidence of cracking on FDOT concrete pavement replacementslab projects. Field slabs were instrumented for data acquisition from high-early-strength concrete pavementreplacement slabs placed on projects funded by the Florida Department of Transportation (FDOT). Data were collectedfor three slabs located in Jacksonville, Florida, and Gainesville, Florida. A battery of laboratory tests wassimultaneously conducted on the FDOT-approved concrete mixture designs used in the instrumented field slabs inaddition to mixtures with variable chloride-based accelerator dosage. Temperature and strain data, as well as physicaland thermal data, were acquired from slabs from the construction projects. The physical and thermal data acquiredfrom the field were used for modeling description and verification. Subsequent to the field testing and data acquisition,the slabs were inspected for the presence of cracking. Laboratory testing included as-received materialscharacterization, heat of hydration measurements using isothermal and semi-adiabatic calorimetry for temperature riseassessment, and strength maturity curves for strength assessment. Using ConcreteWorks and HIPERPAV III, thefindings indicated that adherence to the approved mixture design is critical. High placement temperatures and concreteplacement during the day increased concrete cracking potential. Field additions of accelerator in excess of the approvedmixture design were also found to increase the cracking potential