Synthetic Macro-Fibers for Mitigating Distresses in Thin Concrete Pavements

Abstract

Application of Fiber Reinforced Concrete (FRC) in constructing concrete pavement overlaysand new concrete pavements is gaining more attention. However, there has been limited research on quantifying the performance benefits of fiber and its dosage in concrete pavements, specifically in thin concrete pavements. The present study focused on determining the influence of synthetic macro-fibers in keeping the joint performance high for a longer duration of pavement service life and in mitigating thin concrete pavement distresses such as transverse joint faulting and fatigue cracking. Field data was collected from fiber reinforced in-service test sections at the MnROAD test facility, located on I-94 westbound, 35 miles north-west of the twin cities metropolitan area, Minnesota. Field data included, falling weight deflectometer (FWD), environmental strain, transverse joint faulting, international roughness index (IRI), and crack survey data. It was found that joint performance was significantly affected by the inclusion of fibers. High fiber dosage resulted in greater LTE, lower differential displacement, and lower loaded-side displacement. A faulting prediction equation was proposed on the basis of faulting data and statistical relationships. A relationship was also established between the joint faulting and IRI. The distress data analysis indicated that fatigue cracking may not be the dominant distress of the thin fiber reinforced pavements, but the transverse joint faulting is.