Study On Structural Design And Construction Scheme Optimization Of Steel Deck Pavement

Steel bridge deck pavement has been gradually studied in China.China's steel deck pavement covers the world's major typical types of pavement,but the characteristics of and the performance of each pavement program are significantly different.Choosing the suitable pavement program plays a key role in pavement life.Epoxy asphalt concrete is widely used in the steel deck pavement works,but some of the steel deck pavement projects are still subject to blistering,delamination and other distress.The mixing difference between the test process and the actual production process has also led to the difference between the design target and the actual construction effect of the guss asphalt mixture.This paper is based on Mafang Bridge,which with heavy traffic and thin steel plate,and Hong Kong-Zhuhai-Macao Bridge,which with light traffic and thick steel plate.The following research is carried out for the integrated design of steel bridge deck pavement design and construction.First,the characteristics of the pavement under the full cross-section model of the Mafang Bridge and the Hong Kong-Zhuhai-Macao Bridge are analyzed.Mafang Bridge has a thin deck and L-type stiffened pavement structure system.The pavement surface lateral tensile strain is larger above the vertical web,but the lateral shear strain is lower in steel plate bonding course.Hong Kong-Zhuhai-Macao Bridge has a thicker bridge deck and U-shaped rib structure system.The overall pavement surface transverse tensile strain is lower,but the lateral shear strain is larger in the steel plate bonding course.Secondly,the paper comprehensively analyzes the pavement application conditions,pavement structure,climatic and environmental characteristics,traffic load and other pavement application conditions.According to the specification requirement of bridge deck pavement,the steel bridge deck pavement structure scheme was designed.Mafang Bridge program was designed as single-layer full-thickness hot-mix epoxy asphalt concrete,due to the thin deck and heavy traffic conditions requirements.Hong Kong-Zhuhai-Macao Bridge steel deck pavement program is designed as GMA guss asphalt concrete + SMA asphalt concrete,due to thicker bridge deck and light traffic conditions.Third,gradation design,construction control and feasibility verification of the single layer 80 mm thickness of hot mix epoxy asphalt mixture pavement were carried out.Tests show that,the single layer 80 mm thickness of hot mix epoxy asphalt mixture pavement satisfy the requirements of the design specification,and has good homogeneity and integrity.Fourth,the comparative analysis was carried out on laboratory mixing and Cooker mixing GMA pouring asphalt mixture.Tests show that,the optimum asphalt content in objective mix design in the laboratory can be appropriately reduced,which is conducive to improving the high temperature stability of GMA.The influence of mixing temperature on the performance of GMA mixture is not obvious in the range of 220~240?.Comparing the performance of the laboratory with the Cooker mixing,the aging rate of the asphalt mixture mixed in the laboratory is faster than that of Cooker.The difference in the construction time window and the control index of the GMA mixture between laboratory mixing and Cooker mixing was existed,and the technical parameters determined in laboratory were optimized according to the actual effect of Cooker mixing.The steel bridge deck pavement engineering should analyze the steel bridge deck structure,traffic load,climate and environment,and take into account the pavement engineering characteristics,construction controllability and so on,and further optimize the design of the pavement construction.Through the integrated design of the steel deck pavement program,the durability of steel bridge pavement is achieved.