The long-term evolution of asphalt mixture stiffness in the field represents a complex processwhere three main factors play an essential role: damage, aging and densification under traffic.In order to adequately take them into account, not only must the level of each of these threefactors be known, but also how each particular level modifies the modulus of the asphaltmixture for the temperature and frequency range corresponding to field conditions.The research herein presented is based on experimental data from four flexible sections testedat the CEDEX test track. The stiffness of the asphalt layer was periodically evaluated bymeans of falling weight deflectometer back-calculation and by conducting dynamic modulustesting in laboratory. 1,323,600 loads were applied on the pavements during a 28-monthperiod. This caused a high level of deterioration in all sections as well as a significant asphaltdensification, and also provided time for some aging effects to develop.Based on the results from this full-scale test, different conclusions could be deducedconcerning the evolution of damage, aging and densification and how this evolution modifiesthe stiffness of the asphalt mixture. Special attention has been paid in order to quantify theeffects in terms of changes in the parameters of the original master curve.The model and methodology incorporated in CalME design procedure were successfully usedto reproduce the evolution of asphalt layer modulus during the test. In particular, theassumptions of this model regarding how the dynamic modulus master curve is modified byeach of the three factors were found to be valid for this experiment.
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