Investigation of the MEPDG for Use in Oklahoma Concrete Pavements

Abstract

The Oklahoma Department of Transportation (ODOT) wants to implement the Mechanistic-Empirical Pavement Design Guide (MEPDG) to design pavements. But before implementing the MEPGD it is necessary to understand which design parameters are the most sensitive. The Impact of these parameters in terms of change of pavement thickness was carried out. Further to improve the input parameters in MEPDG, it was decided to obtain actual shrinkage and strength values for typical Oklahoma pavement mixtures. From sensitivity analysis it was seen that several variables made much more impact than expected and also several variables behaved in ways that were unexpected. Furthermore, the equations and the processes used to calculate the performance of the pavements should be more transparent and easier to understand to the users of the software. Shrinkage mixtures that were tested are under the acceptable or typical shrinkage range. Shrinkage testing is still in progress and the final ultimate shrinkage results are expected after 64 weeks. For flexural strength, relationship between flexural stress and compressive stress i.e. M.R = was checked. The majority of specimens had the "k" value close to 9.5, which is acceptable according to MEPDG. Also all the flexural stress graphs showed typical concrete beam behavior under bending and reasonable strengths.