Interlaminar Mode-I Fracture Characterization Underwater of Reinforced Bituminous Specimens

In order to investigate the interlaminar mode I fracture behavior of pavements, Wedge Splitting Tests (WST) have been developed for specimens extracted directly from field sections. As part of the French SolDuGri project focusing on bituminous pavement reinforced by glass fiber grids, WST are applied under static loads and different climatic conditions. This paper highlights the impact of water on such an interlaminar bond characterization. Results derived from samples of five to ten specimens (unreinforced or reinforced with two types of grids) tested under each type of conditions are reported here. The Digital Image Correlation (DIC) technique has been used herein. Depending on the glass fiber grid used, the observation of fractured interfaces and splitting force-crack mouth opening displacement (CMOD) curves does reveal differences. The presence of water in the bituminous emulsion influences on the dispersion of results depending on some type of interfaces. These interlaminar mode-I fracture characterizations should yield greater insight into results recently obtained from accelerated pavement tests conducted on the IFSTTAR fatigue carousel.