Several Mechanical Problems Analysis Of Steel-Girder Bridge Pavement

Long-span steel bridges play important role in highway transportation. The quality of pavement directly affects the cars'comfort and the safe usage of bridge. Currently, the bridge deck surfacing is one of the crucial techniques of long-span steel bridges construction. Compare with the general road, bridge pavement has special structures, such as orthotropic bridge system and light-minded asphalt surface. The pavement diseases are resulted from the influence of environment climate and temperature. Its mechanism can due to the mechanical property of pavement system and the damage accumulate in the asphalt concrete. According to above, the theory analysis and numerical simulation and such methods are used in this dissertation for the analysis of several mechanical problems in steel girder bridge system.First, the structure composing, strength mechanism, mechanics characteristic and engineering applications of SMA (Stone Mastic Asphalt) are detailed introduced and analyzed.Secondly, the orthotropic steel bridge pavement system with close-trapezoid-stiffened ribs is used widely, look it as an object to study. The property of pavement system under dead load is analyzed with numerical simulation method. The sensitivity of pavement surface deformation is analyzed to the variation of Trapezoid Stiffened Rib's three parameters. The distribution pattern of transverse tension stress for different pavement material models and different loading positions are also studied.Thirdly, considering the steel bridge pavement system's mechanical property of pavement cracks, decks and ribs, it can be simplified into a model of composite beam under some condition. The damage accumulation in the asphalt concrete and the control equations of fatigue damage are studied. The prediction method of fatigue life for pavement is discussed initially.Lastly, nonlinear properties of asphalt material such as viscous-elastic-plastic are considered. The plastic accumulation in the asphalt concrete pavement surface under different cyclic load levers and traffic in normal and overload conditions is studied with a elastic-plastic model The relation between the deformation accumulation and time is also numerical analyzed with a creep model.The conclusions of this dissertation can be used straightly on the design of bridge structures and bridge pavement, and as a base for further analysis.