Modelling of the Fatigue Damage of Geogrid Reinforced Asphalt Concrete

International audienceThis paper presents a modelling approach to predict the fatigue damage of glass fibre grid reinforced asphalt concrete in the fully reverse four point bending test (4PB) configuration. The objective of the presented study is to predict the fatigue damage of a composite material made of asphalt concrete and geogrid, using a damage model proven for asphalt mixes. The non-local damage model of Bodin, implemented in a finite element code, is used. Parameter identification is performed with 4PB test results of non-reinforced asphalt concrete beams. A unique model is developed and three analyses are performed for both non-reinforced asphalt (NRA) and geogrid reinforced asphalt (GRA-100 for a 100 kN/m grid reinforced asphalt and GRA-50 for a 50 kN/m grid reinforced asphalt) in the 4PB fully reverse fatigue test configuration with five-layer beams. A comparison between the predicted and the experimental fatigue damage curves (GRA-100 and GRA-50) indicates that the finite element model is able to predict the fatigue behaviour of geogrid reinforced asphalt mixtures