Although dowel bars are an essential design feature of jointed concrete pavements (JCP) to prevent pumping and faulting, limited studies that deal with the constructability of dowel alignment have been conducted. With the emergence of MIT Scan-2 as a non-destructive, robust method of locating dowels, it is now possible to efficiently evaluate construction quality ofdowel bar placement, without damaging the newly constructed pavement. This paper presents a brief review of the results of recent field studies that are aimed at examining the constructability of doweled joints in concrete pavements. The dowel bar alignment data collected in this study encompasses a wide range of design and environmental conditions, and shows thatalignment within reasonable levels, considering equipment, mix design, aswell as workmanship and consistency is achievable in the field. Distressand performance analyses show that within these levels of misalignment, the pavement performance is not significantly affected. However, since construction errors are not uncommon, it is also reasonable to evaluate the effects of misalignments outside the typical tolerance limits. A comprehensive evaluation of the effects of dowel bar misalignment on pavement performance was conducted under NCHRP Project 10-69 to provide guidelines on dowel placement tolerance.
Abstract