Assessment of Iowa Climatic Data and Its Integration into the AASHTO Mechanistic-Empirical Pavement Design Procedure

As the academic community and transportation paving industry address mechanistic design methods, climatic conditions must be considered with much more depth and sophistication. Pavement temperatures must be modeled in discrete, consecutive intervals to evaluate performance over time in different situations. The Enhanced Integrated Climatic Model (EICM) has been developed for this function, and is currently used in the New Design Guide. The EICM has been validated only on a limited basis, and further comparison of outputs with actual field conditions has been recommended. This validation has been limited by the scarcity of field sites where pavement temperature has been gathered simultaneously with the numerous inputs to the EICM. Research objectives are twofold: Develop a database of Iowa weather conditions consisting of the relevant data utilized by the EICM including moisture (rainfall), temperature, wind speed, depth to water table, and sunshine. This data could be used to develop reliability based temperature and moisture profiles for the state of Iowa. It is expected that the water table will need to be used on a site specific basis, whereas that is likely not necessary for the other EICM input parameters. Verify the EICM model based on Iowa conditions.