Mixed-Mode Debonding Approach to Evaluate Water Sensibility in Bi-Layer Composite Pavement

In order to evaluate water sensibility on the interface between layers of composite pavements, a four-point bending (4PB) test on bilayer structure in a water bath is proposed. Using the virtual crack closure technique, the individual strain energy release rates are calculated with a specific model. The debonding mode I should be recognized as the main failure mode. For bilayer specimens made of a cement concrete overlay on bituminous material, the specific test has shown a competition between the different failure mechanisms. A very good bond resistance between layers compared to the fracture tension resistance of the cement concrete layer is observed. In this work, first results of the effect of water on the behavior of such a material interface are presented. An aquarium is built in order to submerge under water the bi-layer specimen. The final fracture length of the specimens, curves of force-displacements and first digital image correlation results show the influence of water immersion on the debonding failure mode.