NCHRP 10-69 Guidelines for Dowel Alignment in Concrete Pavements

Principal Investigator(s):

Lev Khazanovich, Former Professor, Civil, Environmental and Geo-Engineering

Project summary:

Dowels are used in jointed portland cement concrete pavements to provide load transfer, reduce faulting, and improve performance. They are either placed manually before concrete placement or during construction by automatic dowel bar inserters; however, inspection of pavements in several states has revealed that misalignment of dowels generally occurs regardless of placement method. These inspections also revealed that slab cracking and other forms of distress might not always occur as a result of such misalignment. Since only limited research has been performed to determine the extent of dowel misalignment in pavement construction and its effect on performance, the objective of this project was to develop guidelines for dowel alignment in concrete pavements that addressed all forms and combinations of dowel misalignment (i.e., vertical and lateral skew and displacement). Under this study, the University of Minnesota team created procedures for estimating the short- and long-term effects of different levels and types of misalignment on pavement performance. Using these tools, the research team then developed guidelines for dowel alignments in concrete pavements that are theoretically sound and supported by laboratory and field data.

Project details: