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

摘要

In an attempt to better understand and predict concrete pavement behavior, theincorporation of material and climatic factors in mechanistic-empirical design methods isfast 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 criticaldistresses and fatigue life of rigid pavements. A mechanistic analysis and designsoftware (RadiCAL) was developed employing an influence line approach in conjunctionwith Miner???s Hypothesis to calculate the fatigue damage at numerous locations in theslab for typical jointed plain concrete pavement sections. Permanent built-in curling ofconcrete slabs, stress range-based concrete fatigue transfer functions, and the inclusion ofself-equilibrating stresses from non-linear temperature profiles were found to haveconsiderable effects on the predicted location and magnitude of concrete fatigue damage.A parameter named NOLA (Non-Linear Area) was developed and implemented inRadiCAL to provide a simple, visual method to account for these self-equilibratingstresses that are readily ignored in pavement analyses. Top-down and bottom-uptransverse, longitudinal, and corner cracking were found to be critical fatiguemechanisms depending on the pavement geometry, climatic zone, and materialparameters selected. These results are in contrast to the assumed bottom-up, mid-slabtransverse cracking mechanisms, which are exclusively predicted using traditionalmechanistic-empirical techniques. These predicted fatigue failure modes and locationscorrespond well to the wide variety of observed fatigue cracking patterns on existingrigid pavements sections in California and show promise for calibration and designadaptation in other regions as well. Results show that the use of doweled transversejoints will reduce the likelihood of these alternative cracking mechanisms significantly.The exception to this is with the use of widened slabs where the predominant predictedfatigue cracking mechanism in RadiCAL remains longitudinal cracking regardless of loadtransfer levels at the transverse joint.