Sensitivity Index comparison of pavement mechanistic-empirical design input variables to reflective cracking model for different climatic zones

One of the main types of distress observed in Asphalt Concrete (AC) overlays is reflective cracking, and a reflective cracking model has been recently incorporated into the latest released version of AASHTOWare Pavement ME Design (PMED) software. This study documents the complete results of the sensitivity with respect to the design inputs and material properties of reflective cracking distress predicted by the PMED software. Six representative locations distributed across different climate zones of the United States were considered for studying the effects of climate extremities on changes in predicted reflective cracking distress. One-at-a-time (OAT) sensitivity analyses was performed to determine the Normalized Sensitivity Index (NSI), with two scenarios considered for OAT analyses: (i) sensitivity of short-term reflective cracking prediction (i.e., the year when predicted distress reached 4000 ft/mile) and (ii) sensitivity of long-term reflective cracking prediction (20-year design life). The summary of NSI ranking for varying traffic levels are presented.