Abstract:

In order to reveal the effect of seasonal temperature variation in the areas with large temperature difference on the performance of asphalt pavement,this paper takes into consideration the time-temperature viscoelasticity of asphalt concrete,and performs numerical simulations to analyze the dynamic behavior and performance under moving vehicle load and seasonal temperature variation for two kinds of typical asphalt pavement structures.One is the structure with a semi-rigid base layer containing cement-stabilized macadam ( structure S1) and the other with a flexible base layer containing graded aggregate materials ( structure S2) .The results show that ( 1) with the increase of axle load,the decrease of dynamic load frequency,the change of horizontal thrust direction from the opposite to the same direction of the moving vehicle,or with the deterioration of interlayer conditions,the stress at the bottom of the asphalt layer generally increases，while the fatigue life gradually decreases; ( 2) the variation of pavement temperature distribution significantly influences the tensile stress of each structural layer in summer but slightly influences the stress in winter; ( 3) at the bottom of the surface layer,the tensile stress in summer or at high temperature is less than that in winter or at low temperature,while the base layer shows an opposite trend in this regard; and ( 4) although the fatigue lifetime of the asphalt layer of structure S1 under various age and temperature conditions is longer than that of structure S2,it has a deficiency of drastic fluctuation,while S2 has a relative stable fatigue behavior and a superior environmental adaptability.

Key words: asphalt pavement, temperature load, vehicle dynamic load, coupling, dynamic behavior, fatigue property