Mechanics And Structural Combination Study Of Asphalt Pavement On Wuhekou Long-Span Concrete Bridge

The quality of asphalt pavement on concrete bridge deck directly influences the safety and comfort of driving, endurance and investment of the bridge. This paper studies about the asphalt deck pavement of WuHeKou Bridge by the ways of practice investigating, theory analysis and testing.Firstly, the pull stress (strain) in deck pavement and shear stress in and between layers, which are caused by the static vehicle load on the different surface locations, are computed in order to determine vertical and horizontal disadvantage locations of the maximum stress and strain on deck pavement. Then the mechanics situations with different modules of upper and lower layers are compared so as to put forward proper module ratios for that bridge.Secondly, the vehicle load is simplified to be a kind of moving evenly distributed load. Then the pull stress (strain) in deck pavement and shear stress in and between layers, which are caused by the dynamic vehicle load on the different surface locations, are computed as well. And these results are compared with the static ones. The stress in deck pavement is then computed with vehicle speed being altered. The horizontal shear stresses with different depth in deck pavement are compared in the state of braking. Besides, the influence of horizontal stress index to horizontal shear stresses is researched.Thirdly, the asphalt mixture of deck pavement is designed in this paper. Four types of gradation (AC20 redesigned, fiber AC20,SMA13 and SMA10) are chosen, whose optimum asphalt contents are tested by Marshall Method. Then all the performances of the four types of mixturesare are checked out, as well as the asphalt mixtures modified by three types of additives (LF8000,TPS and Sasobit). Compound rutting tests and compound beam fatigue tests are designed to simulate the real situation of deck pavement more accurately so as to provide the theory base for choosing the materials and structures of WuHeKou Bridge deck pavement.Finally, the design of waterproof and cohesive layer is illuminated and instructed, as well as the construction of asphalt concrete pavement. And the practice of oscillatory compaction machine in long-span concrete bridge is studied.