Investigation of the Rutting Evolution of Double-Layered Heterogeneous Asphalt Pavement on a Steel Bridge Deck under the Coupling of Heavy Load and Variable Temperature

This paper studies the rutting evolution of a gussasphalt (GA) and epoxy asphalt (EA) composite structure under the coupling of heavy load and variable temperature for a double-layered heterogeneous pavement structure of long-span steel bridge. First, the rheological properties of the GA and EA mixtures were evaluated by conducting a permanent deformation test under triaxial repeated loads. The creep parameters for the GA and EA mixtures were determined by multiple linear regression based on the Bailey-Norton creep model. Then, the real traffic volume and temperature distribution of the GA+EA composite pavement structure on a long-span steel bridge in summer were obtained, and the permanent deformation evolution laws of the GA+EA composite pavement structure under different loading and temperature conditions were simulated using a finite-element (FE) method. The results show that the GA+EA structure has excellent rutting resistance performance. The rutting depth value estimated under constant temperature is exaggerated to some extent compared with that estimated under variable temperature condition. When the tire-pavement contact pressure increases from 0.7 MPa to 1.4 MPa, the rutting depth of GA+EA structure increases by about 110%. Findings from this study are helpful to investigate the rutting characteristics in the steel bridge deck pavement (SBDP) and may be used in the design of SBDP materials and structures.