Dynamic Response Of Asphalt Pavement On Vehicle-Road Interaction Test Section

With the rapid development of Chinese highway construction, the asphalt pavement has been used widely. However, with the growth of vehicle, the phenomenon of pavement premature failure is becomed more serious. In order to find out the reasons for the pavement premature failure more in depth, the study of stress and strain distribution from pavement layers becomes necessary. This paper combines experiment with simulation to analyze stress and strain distributions from layers of asphalt pavement. The main research contents and results are as follows:(1) Applied the traditional design method of pavement to design and calculate the test sections. In order to reflect the true response of layers, the asphalt pavement is built under the current conditions. The walking mechanism of tire rotating around the fixed axis is installed to simulate the vehicle traveling on the road. Besides, the pavement test system based on the component of optical fiber data acquisition is built to collect the stress and strain from each layer of pavement.(2) Used the Vehicle-Road coupled test section to carry out experimental study.With the effect of standard tire pressure, four different speeds are selected to compare and analyze dynamic response from every layer of asphalt pavement. It concludes that the value of strain from layers of asphalt pavement shows a decreasing trend with the increasing speed. In addition, three different tire pressures are selected in the same speed to compare dynamic response from every layer of asphalt pavement. It concludes that the value of strain from layers of asphalt pavement increases with the increasing tire pressure.(3) Utilized the software of ABAQUS to develop the 3D finite element model of road according to the parameters of test sections. This road model is used to calculate the response from every layer of asphalt pavement under the static load.The pavement deflection, vertical displacement and vertical compressive stress are selected as evaluation indexes to analyze the road response by changing the axial load and the tire pressure. Be obtained that these evaluating indicators show anincreasing trend with the increasing tire pressure and size of axial load. And the model size has nothing effect to the road response with the same boundary condition.(4)It proposes the method of a moving load platform to keep the load moving on the road model. The simulation data and experimental data are compared to validate the reasonable of the road model. It uses this model to calculate these evaluation indexes including vertical pressure, longitudinal strain, transverse shear strain, longitudinal shear stress and longitudinal shear strain. It studies the influence on dynamic response of pavement structure from speed, axle load and tire pressure respectively. It achieves that all above indicators show an increasing trend with the increasing tire pressure and size of axial load. However, these indicators show a decreasing trend with the increasing speed.