Dynamic response of temperature-seepage-stress coupling in asphalt pavement

摘要

Temperature-seepage-stress coupling exists in asphalt pavement and directly affects force and failure mechanisms in the pavement structure. The objective of this paper is to propose a systematic approach to simulate the dynamic characteristics of asphalt pavement, under the combined effects of vehicle dynamic load and environmental factors. In the simulation, the asphalt viscoelastic constitutive equation was established using Burger's model, to derive the nonlinear control equation of thermal-hydraulic mechanical coupling of asphalt pavement. Then, a finite element model of asphalt pavement was built using the software ABAQUS. The thermal stress and pore water pressure in pavement structure were analyzed under the condition of rainfall infiltration. Moreover, vertical stress, longitudinal stress, transverse stress and shear stress of different structural layers were analyzed and computed under the multi-field condition. These stresses were then compared to the stresses in the single stress field. The results show that when seepage and temperature are considered, stress change of the subbase is insignificant. However, the transverse stress in the modified fine-grained asphalt concrete layer (AC-1) and the vertical shear stress in the asphalt macadam layer (AM) increased 30% and 53% respectively, compared to the single stress field. This would lead to the occurrence of rutting and cracks in asphalt pavement, which accordingly seriously affects the road performance in hot and rainy weather. The field test was carried out in the DaGuang Highway, and the validity of the simulation model was verified. (C) 2019 Elsevier Ltd. All rights reserved.