Evaluation of elliptical, glass fiber reinforced polymer, and stainless steel dowel bars in concrete pavements with consideration to subgrade resilient modulus.

摘要

Jointed plain concrete pavements use dowel bars to transfer load across transverse joints. The job of the designer is to optimize the number, size, and location of the dowels in a given pavement. This research used data from two different construction locations. The first project evaluated the performance of standard 1.5 inch round and elliptical shaped dowel bars at different spacing intervals using full dowel baskets. The performance potential of standard 1.5 inch round and elliptical dowels placed in the wheel paths only was also evaluated on the same project. The second project compared corrosion resistant dowel bar (stainless steel and glass fiber reinforced polymer (GFRP) dowel bars) performance to round 1.5 inch epoxy-coated steel dowel bars. The stainless steel and GFRP bars are for possible use in environments where steel corrosion may be an issue.;Performance data was measured on both projects in terms of deflections, using falling weight deflectometer (FWD) data collected biannually. Joint faulting data was collected over the five-year test period for both projects. Roughness data was collected for only the elliptical dowel bar project over the five-year test period. Resilient modulus values were found by triaxial testing of the pavement subgrade samples. Performance criteria graphed verses resilient modulus allowed for the comparison of different dowels as the subgrade resilient modulus changed.;The elliptical dowel bar study indicated medium elliptical dowel bars at 12 inch or 15 inch spacing perform equally to the standard 1.5 inch round dowel bars at 12 inch spacing. The elliptical study also indicated the potential use of medium elliptical dowel bars in wheel paths only. The corrosion resistance study indicated stainless steel dowels spaced at eight inch intervals were the only dowels to outperform the 12 inch spaced round 1.5 inch epoxy-coated bars.