Development of Mechanistic-Empirical Principles for Jointed Plain Concrete Pavement Fatigue Design

In an attempt to better understand and predict concrete pavement behavior, the incorporation of material and climatic factors in mechanistic-empirical design methods is fast becoming a necessity. With the wide range of climatic regions in the United States, the inclusion of localized factors can have a profound effect on the observed critical distresses and fatigue life of rigid pavements. A mechanistic analysis and design software (RadiCAL) was developed employing an influence line approach in conjunction with Miner???s Hypothesis to calculate the fatigue damage at numerous locations in the slab for typical jointed plain concrete pavement sections. Permanent built-in curling of concrete slabs, stress range-based concrete fatigue transfer functions, and the inclusion of self-equilibrating stresses from non-linear temperature profiles were found to have considerable effects on the predicted location and magnitude of concrete fatigue damage. A parameter named NOLA (Non-Linear Area) was developed and implemented in RadiCAL to provide a simple, visual method to account for these self-equilibrating stresses that are readily ignored in pavement analyses. Top-down and bottom-up transverse, longitudinal, and corner cracking were found to be critical fatigue mechanisms depending on the pavement geometry, climatic zone, and material parameters selected. These results are in contrast to the assumed bottom-up, mid-slab transverse cracking mechanisms, which are exclusively predicted using traditional mechanistic-empirical techniques. These predicted fatigue failure modes and locations correspond well to the wide variety of observed fatigue cracking patterns on existing rigid pavements sections in California and show promise for calibration and design adaptation in other regions as well. Results show that the use of doweled transverse joints will reduce the likelihood of these alternative cracking mechanisms significantly. The exception to this is with the use of widened slabs where the predominant predicted fatigue cracking mechanism in RadiCAL remains longitudinal cracking regardless of load transfer levels at the transverse joint.University of California Pavement Research Center, California Department of Transportation, Illinois Department of Transportationunpublishedis peer reviewe