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This report presents the development of simulation software for modelling dynamically loaded pavement response. The analysis is carried out by employing the finite element method and by integrating the resulting discrete equations of motion through the central difference method. The lower pavement layers (base, subbase and subgrade) are assumed to be elasto-plastic and are described by using the flow theory of plasticity. The mapped infinite elements are used instead of viscous boundaries to mitigate the wave reflection from the boundaries of the model. The predicted pavement responses are compared with the experimental results obtained by a Falling-Weight Deflectometer (FWD). Dowel bar load transfer mechanism is also analyzed.

This report works to identify potential mechanisms for the occurrence of top-down cracking, as well as to investigate stress patterns and concentrations due to surface load and preexisting transverse (thermal) cracks. It attempts to provide information on surface stresses that derives from both theory and experiments. In particular, contact mechanics solutions are analyzed to gain information on loads that are subsequently used in performing numerical evaluation of surface stresses. Examples of three-dimensional computations using the finite element code ABAQUS illustrate the analysis, and comparisons of stresses for uncracked and cracked pavements are made. The report concludes that the presence of a transverse crack in the asphalt concrete (AC) layer significantly increases the vertical stresses in the base. It also has a noticeable effect on the horizontal stresses in the AC layer.

The primary objective of this project was to provide Mn/DOT with assistance in validating the Mn/ROAD database. The research approach consisted of the following: - review the Mn/ROAD data acquisition systems and data collection procedures, - evaluate the performance of the online and offline dynamic sensors, - validate the online dynamic data collection and database - validate the online static sensors and database, - propose activities and procedures to ensure that future data are reliable.