Asphalt Pavement Rutting Behavior Simulation And Prediction

With continuous increase of highway transportation volume and heavy load vehicles, asphalt pavements rutting damage has been becoming more serious, which severely influences the vehicle safety and it’s comfort. Study on the rutting problem of the asphalt pavement becomes a very hot research topic. Anti-rutting asphalt concrete a new pavement material, can effectively improve the rutting resistance with its higher modulus, better rutting resistance, better water resistance, weaker temperature sensitivity and better fatigue performance. The commercial finite element method(FEM) software AnsysTM was employed for the numerical analysis of the mechanical response of the semi-rigid base asphalt pavement. First, 3-D element model of asphalt pavement structure was established based on the elastic mechanic. The proper layer design of anti-rutting asphalt concrete is determined by analyzing the mechanical response when anti-rutting asphalt concrete layer in different structure position. The effects of anti-rutting asphalt concrete modulus the layers thickness and axis load on pavement structure stress, strain, and deflection was further analyzed. Results indicated that anti-rutting asphalt concrete has better resistance to the rutting damage and reasonable modulus range is recommended. Secondly, asphalt pavement model had been established for simulation of the rutting based on reasonable supposition and viscoelastic theory. Parameters of anti-rutting asphalt concrete with different additive usages were determined by uniaxial compression creep test. By numerical simulation,it was found that the temperature, axle load, number of load, content of admixture and surface thickness have great influence on the rutting depth. Finally, it were good ideas that shear parameters and rutting depth should be added to pavement design indexes system by analyzing and calculating shear stress and rutting depth based on mechanics of the formation of asphalt pavement rut.