Analysis Of Time-history Responses Of Layered Asphalt Pavement Structure Under Moving Load

The research of the interaction system between the vehicle and pavement on the highway is an important subject in the field of road. In order to meet the structure design of asphalt pavement and the need of application and development, based on the theoretical analysis, the multi-storey elastic pavement structure is studied with the basic methods of dynamic finite element, and the ANSYS software is applied so as to analyze the time-history responses of layered asphalt pavement structure under moving load and find out the laws and characteristic of dynamic responses. The main research results of this paper are as follows:1.The power spectrum density of road roughness is analysed, and on the basis of power spectrum density, the frequency domain model and time frequency domain model of road roughness are introduced and summarized;2.The quarter vehicle harmonic load model is adopted as the basis of the analysis of moving load. Based on the current research and elastodynamics theory, combining ANSYS software, the numerical methods of dynamic finite element equations are concluded;3.According to the assumption of elastic layered asphalt pavement, a three-dimension dynamic finite element model is established with ANSYS software and the time-history responses problem (dynamical shift, dynamical stress and dynamic strain) are analysed in theory under the vehicle moving load to find out the change trends and regularities of the dynamic response, the influence of speed, load and temperature are focus on discussed, and also the comparison of pavement response under static load, dead load and dynamic load are added. The results illuminate that dynamic load model can describe the actual mechanics characteristic of pavement structure more accurately.4.The numerical simulation results are compared with the measured values (dynamical strain and dynamic stress). Through analysis and evaluation, the numerical simulation results are coincident with the measured values. The results show that the research ideas and the model are reasonable.