Research On Crack Resistance Performance Of Asphalt Mixture Based On Discrete Element Method

As a flexible pavement,asphalt pavement has been widely used in domestic and foreign countries due to its numerous advantages.However,during the service life,asphalt pavement is often subjected to the effects of vehicle loads and natural conditions,which frequently leads to the appearance of many small cracks before the end of its service life.The cracks connect and expand into larger cracks with time evolution,which not only affect driving comfort but also cause rainwater infiltration and accelerate the destruction of the pavement structure.In this paper,the impact of various factors on the anti-cracking performance of asphalt mixture was studied using a comparison analysis of tests and discrete element numerical simulations.The asphalt mixture was subjected to gradation,and four types of mixtures were compared and analyzed with the Marshall test to determine the optimal oil-stone ratio and void ratio for different gradations.Then,semi-circular specimens were prepared using the compaction method,and the specimens were subjected to semi-circular bending tests on a universal testing machine.The bending test was further simulated by the discrete element method,and different forms of coarse aggregates were selected by observation.By performing three-dimensional scanning technology to process coarse aggregates,different shapes of solid models are obtained.Subsequently,the model was imported into the EDEM for particle filling.The mass volume of each component in the specimen was calculated according to the indoor test conditions,and a semi-circular specimen was generated in the EDEM for bending test.Finally,the present analysis was made by comparing the test results with the discrete element numerical simulation to investigate the effects of test loading rate,prefabricated crack depth,and mixture gradation on the anti-cracking performance of asphalt mixture.The influence of interfacial adhesion on the cracking resistance of asphalt mixtures was investigated using discrete element software.