Dynamic Behavior Of The Temperature And Load Coupling Effect On Asphalt Pavement In Plateau- Cold Region

Currently, asphalt pavement structure is the main form of highway pavement, with the increasing of the loading and speed of the highway transportation, the service life of asphalt pavement road transport serious shortage, this has become a problem that restricted the development of China’s highway. Therefore, this thesis carries out studies aiming at the dynamic mechanical behavior of different types of asphalt pavement structure, according to exploring the damage mechanism of the pavement structure, and optimizing the structure of a combination of road, thereby increasing pavement life, this has important engineering significance. This paper takes two kinds of typical asphalt pavement structure which contains semi-rigid base and flexible base as research objects, and conducts a systematic research on dynamic performance of asphalt mixture, temperature behavior of asphalt pavement and asphalt pavement’s dynamic behavior feature under the effect of temperature dynamic coupling. The main research works are as follows:(1) Through developing dynamic modulus uniaxial compression test of three kinds of asphalt mixture which contains SMA-13, AC-20and AC-25, this can obtained asphalt mixture dynamic modulus and phase angle of different temperatures and frequencies, and by combining with approximate methods, it can fit the relaxation modulus master curve and time-temperature shift factor, and on this basis the viscoelastic parameters of asphalt mixture were reached, it provides material parameters based on measured data for numerical simulation later.(2) To study the temperature behavior of asphalt pavement structure in Alpine regions, by taking ABAQUS software as computing platform and combining with the orthogonal test method and temperature hysteresis attenuation model, then carries on the analysis of the meteorological parameters’influence on asphalt pavement temperature field and its sensitivity to parameters, and discuss structure type, pavement layer thickness and the inter-layer condition and other factors’effect on pavement temperature field and thermal stress distribution, and predict the different depth temperature’s diurnal variation of asphalt surface.(3) Through considering the impact load characteristics of fixed point and mobile load characteristics, then can establish the asphalt pavement structural dynamic response three-dimensional finite element model, and take the virtual temperature field data as temperature distribution of asphalt pavement to study and analyze the axle load, speed, inter-layer condition, temperature time and other elements’effect on dynamic response of road surface under load, and by combining with the multiple regression analysis can establish its dynamic index layer structure and fatigue life prediction model.(4) By comparing impact dynamic response of pavement structure under load and moving load, then can analyze different load model’s effect on the responses and its rationality, it make a referential exploratory job for further proposing reliable load mathematical model.