Analysis Of The Dynamic Response Of Asphalt Pavement Under Traffic Loads

With the rapid development of our country economy and the progress of science and technology, the asphalt pavement structure gets more and more broad application.In recent years, the asphalt pavement has become one of the main forms of highway pavement structure in our country. But attendant problems are vehicle increasing , over load-driving and over speed-driving getting more and more worse, and the early injury of the asphalt pavement structure becoming more and more seriously. Besides, vibration is often caused by vehicle runs on the roads because pavement irregularity. The force that is given to the road changes with time and road face characteristic, it is a typical dynamic load. So it is a necessary trend that the theory of pavement design changed from a static system to a dynamic system.In response to the above problems, a typical asphalt concrete pavement structure was selected to establish in this paper, and the dynamic response of asphalt pavement under traffic loads is analyzed by using the three-dimensional (3D) finite-element method and finite element analysis program ANSYS. We calculate the dynamic stress, strain and displacement respectively about the asphalt pavement structure under different ways to load, different loads, and different speed, and get the influence and some rules. The main contents are as follows:(1) Movable invariable loads are decided to simulate traffic loads on regular pavement, and the asphalt pavement model is also simplified a 3D model. ANSYS is used to establish model and analysis the transient dynamic response.(2) Moving and time-harmonic loads and moving vibration loads are decided to simulate traffic loads on irregular pavement, and ANSYS is used to establish model and analysis the transient dynamic response.(3) Foundation dynamic response to the pavement structure under all kinds of situation such as different load, different speed and so on are analyzed, and the attenuate law of dynamic stress, dynamic strain and the displacement under different depth of expressway on the action of traffic load is gained.Through the analysis in this paper we get some conclusions, which can be used in design, building operations and management of asphalt pavement engineering. They will give some theoretical significance and references in the future.In this paper, there is a point of innovation: that is a more actual vibration load is designed by vibration theory knowledge which based on that the asphalt pavement is a known waveform.