Study On Damage Characteristics Of Asphalt Concrete Crack Repaired Composite Structure

Because of the advantages of convenient construction and comfortable driving,Asphalt Concrete(AC)pavement is widely used in advanced highways all over the world.Act on load and environmental factors,it is easy to occur crack and other diseases in the stage.At present,cracks in asphalt pavement are mainly repaired by caulking.But it is prone to secondary damage during its service because of the poor cooperative performance between repaired materials and asphalt concrete.Therefore,finding out the performance decay law of asphalt concrete crack repaired composite structure in different environments has great practical significance for improving the crack repaired technology of asphalt pavement and prolonging the service life of asphalt pavement.In this thesis,epoxy resin glue and EA/PU IPN have been used to repair vertical cracks and V-shaped cracks.The performance decay law of AC crack repaired composite structures under different temperature environment or under water with different temperature were studied by uniaxial compression test and bending test.At the same time,AC crack repaired composite structures’damage prediction model of bending performance were established by using the Logistic method.It could provide a theoretical basis for improving the performance evaluation criteria of crack repaired composite structure by using damage prediction model.The main coclusions of this thesis are as follows:(1)The damage characteristic of uniaxial compressive performance of AC crack repaired composite structures under environment and water with the temperature of 30℃,40℃,50℃,60℃ were proved.The results showed that compressive strength and compressive failure stiffness modulus of each crack repaired composite structure were on downward trend with the increase of temperature.Moreover,the damage degree of crack repaired composite structures under water were more than the same specimen under temperature.(2)The damage characteristic of bending performance of AC crack repaired composite structures under environment and water with the temperature of 5℃,10℃,15℃,20℃ were proved.The results showed that flexural strength and bending failure stiffness modulusof each crack repaired composite structure were on downward trend with the increase of temperature.And the damage degree of crack repaired composite structures under environment were more than the same specimen under temperature.(3)The effects of crack morphology and crack repaired materials on the performance of crack repaired composite structure were studied.The results showed that the uniaxial compression performance of vertical crack repaired composite structure was better than V crack repaired composite structure.Epoxy resin repaired composite structures’ uniaxial compression and bending performance was better than EA/PU IPN crack repaired composite structure.(4)Logistic damage prediction model of AC crack repaired composite structures’flexural strength at different environment were established,which could provide research foundation for predicting the law of crack repaired composite structures’damage at different environment.