Evaluation of the visco-elasto-plastic behavior of glasphalt mixtures through generalized and classic Burger’s models modification

• Modified Burger’s and generalized models are compared in estimating the VEP.
• Viscoplastic string is added in series with Burger’s and generalized models.
• Modified generalized model has better fitting with the experimental data.
• Modified generalized model approaches very much to the experimental data.
• Modified generalized model cover all of deformation components.

For representing the first two stages of creep phenomenon, both Burger’s and generalized creep models are suitable, however, these models are not enough to describe the third stage. Therefore, for predicting the visco-elasto-plastic glasphalt behavior, a visco-plastic string is added to these two models in series. This study seeks to compare the modification of Burger’s model and generalized model regarding the visco elasto-plastic behavior estimation of glasphalt mixture. For this purpose, a number of repeated load axial (RLA) tests under various temperatures and different stress levels were done. The modified models were then used to estimate the visco elasto-plastic strain and the resulted values were compared against experimental data. The results indicate that compared with modified Burger’s model, the modified generalized model fits better with the experimental data.