Study The Bridge Deck Pavement Scheme Of Fuyuan Road Xiang Jiang Bridge

It is an important subject to pave asphalt concrete directly on concrete bridge deck.At present,the research is mainly focused on the design of pavement structure and selection of pavement materials.To find the relationship between the stress characteristics of asphalt pavement and loading conditions,temperature,climate,pavement materials,the mechanical properties of the bridge structure and the mechanical properties of the bridge and pavement under vehicle load should be analyzed in the design of the pavement structure.In the designing of materials,the water stability,fatigue resistance,high temperature stability,low temperature anti-cracks ability and the bond strength between layers are mainly considered.Through theoretical analysis,laboratory tests and verification of actual engineering project,the pavement of Xiangjiang bridge,which is a laminated beam structure,on Fuyuan Road in Changsha is systematically studied in this paper.Firstly,through investigating the common structures and materials of domestic and overseas concrete bridge deck pavement,three different schemes have been worked out.Then,the effect of the thickness of asphalt layer and the modulus of waterproof and cohesive layer on the maximum shear stress,and the maximum shear stress of different structural layers are researched by mechanical analysis.Finally,it is recommended that the modulus of waterproof and cohesive layer is 70MPa~200MPa,and the thickness of epoxy asphalt layer is 3.5cm~5.5cm.The performance requirements of epoxy asphalt concrete are proposed by laboratory tests.On this foundation,the mix ratio is designed.At the same time,the high temperature stability,low temperature anti-cracks ability,water stability,corrosion resistance ability and ageing resistance ability of epoxy asphalt concrete are comparative studied with those of SBS modified asphalt concrete,cast asphalt concrete and SMA.Meanwhile,the fatigue resistance,low temperature cracking resistance and water damage resistance of domestic epoxy,American epoxy and Japanese epoxy were also studied by laboratory tests.The results show that considering all the performances,epoxy asphalt concrete is the best.As waterproof adhesive layer,the mechanical properties of SBS modified emulsified asphalt,SBS modified asphalt,epoxy asphalt and FYT waterproof material are compared and analyzed.The results show that the shear strength and pull-off strength of epoxy asphalt are obviously greater than those of other kinds of materials.Also,these two performances meet the requirements of vehicle loads.In conclusion,according to the mechanical analysis and laboratory test results from the aspect of pavement structure and materials,the paving scheme of Xiangjiang bridge on Fuyuan Road in Changsha is recommended : epoxy asphalt waterproof and adhesive layer+3.5cm EA-13 epoxy asphalt concrete(basalt)+SBS modified emulsified asphalt adhesive layer+4.5cm SMA-13 modified asphalt concrete(basalt,SBS).Based on the study of the construction technology,the matters needing attention of its construction and quality inspection standards of the pavement are proposed in this paper.