Permanent Deformation in Flexible Pavements

This paper presents a mechanistic-empirical framework for evaluating permanent deformation in flexible pavements. The procedure uses rational material properties and can be used as an analysis tool, as a companion to the design method. The material properties required are (1) the stress dependent modulus of the pavement layers, asphalt concrete and granular base/subbase, and (2) the relation between the accumulated and the resilient strain with the number of load repetitions and stress level. The procedure is a compromise between simple and advanced approaches, between linear elasticity and nonlinear incremental finite element approaches. In addition to this improvement, the proposed procedure uses the “actual” temperature distribution in the asphalt layer at every hour in the whole design period. It is evaluated by computing the rut depth in well-designed pavements. All the results for the pavement response under different conditions are within the expected ranges.