Abstract:To solve the issue of insufficient durability for steel bridge deck pavement, two types of double-layer stone mastic asphalt (SMA) pavement structures were used as research objects in this study. Firstly, the most unfavorable loading position of the typical bridge deck was determined through the finite element analysis method; and the mechanical response of the above two structures at this loading position was calculated, thus the optimal structural combination for steel bridge deck pavement and its design index requirements were proposed. Secondly, two types of high viscosity and elasticity modified asphalt (A and B) were prepared; and then, taken the road performance of asphalt binders and their mixtures as the evaluation criteria, effects of asphalt binder’s types on the road performance of steel bridge deck pavement asphalt mixtures were compared, thus the asphalt binder with the best properties was selected. Finally, the bonding performance between the pavement layer and the steel plate was evaluated by using the indoor pull-out and oblique shear tests. Meanwhile, the bonding performance of the pavement layer under the most unfavorable temperature conditions was tested with the actual engineering. Test results show that the middle position is the most unfavorable load position on the steel bridge deck. Therefore, the tensile stress, vertical displacement, and bottom shear stress of the pavement layer at this location can be selected as the main design indicators for steel bridge deck pavement. In addition, the two designed pavement structures exhibit the consistent mechanical response patterns, among which the vertical displacement and layer bottom shear stress of structure 2 (SMA-13+SMA-10+asphalt mortar) are relatively smaller. As for the asphalt binders, comparing with SBS (Styrene Butadiene Styrene Triblock Copolymer) modified asphalt, the prepared high viscosity and elasticity modified asphalt (A and B) have the better road properties, among which the road property of A modified asphalt is the best. The pull-out test results show that, under the temperature conditions of 25℃ and 60℃, the bonding strength between the pavement layer and the steel plate can all meet the design requirements. The actual engineering test result show that temperature inside the pavement structure layer exhibits the periodic variation pattern, with the highest temperature not exceeding 60℃. Therefore, the design index based on the interlayer bonding strength at this temperature is scientific and reasonable, and meanwhile, the interlayer bonding strength of various structural layers in the actual engineering meets the design requirements under this unfavorable temperatures.