A non-linear elastic material model and its application in pavement design

Resumen

A non-linear elastic material model with a stress level control defined by the Mohr-Coulomb yield criterion has been developed, implemented, and tested in practice. The model is developed for unbound granular base materials in conjunction with relevant test methods. In the design process the material model is used to predict pavement response and theoretically confirm a stabilized behavior in the base material during cyclic loading. Input parameters for the model are directly linked to practical field tests where design parameters can be validated in-situ during the construction of the pavement. Critical parameters are void ratio, isotropic mean stress, and matric suction. The in-situ mean stress is here the accumulated effect of both compaction induced residual stresses and the contribution due to matric suction. The in-situ mean isotropic stress is estimated indirectly from seismic measurements. The matric suction in the unbound granular material is measured with gypsum blocks. The practical usefulness of the proposed model is demonstrated with a case study where the pavement construction is economically optimized based on available materials. Results show that the model can accurately predict the non-linear pavement response based on the material properties measured during construction.