With the further adoption of mechanistic-empirical design methods in the pavement industry, the calculation of critical responses and cumulative damage for a variety of parameters will be imperative. Traditionally, the critical tensile stress developed by loads at the midslab edge has been used as a mechanistic parameter to determine the required thickness in jointed concrete pavements. However, the inclusion of both temperature and shrinkage gradients in concrete pavement analysis can drastically alter the critical stress location and subsequent distress type that predicts pavement performance. Longitudinal and corner cracking have been found in California to be distresses as significant as transverse cracking. Most of the longitudinal and corner cracking can be explained by excessive differential drying shrinkage. Using finite-element analysis, this study compared the critical tensile stress near the transverse joint with the critical tensile stress at the midslab edge (relative reference stress) for California-type jointed plain concrete pavements. The analysis of the data showed that transverse joint loads were more significant in critical stress calculations for a considerable number of input parameters. These loads at the transverse joint can manifest themselves as top-down or bottom-up longitudinal, transverse, or corner fatigue cracks unlike the bottom-up transverse cracks traditionally predicted by midslab edge loads. The likelihood of critical slab stresses near the transverse joint was considerably increased with the use of negative temperature gradients and extended lane widths.
Abstract