Comparative Study On The Prestressing Bridge Specifications Between China And U.S.A

《AASHTO LRFD Bridge Design Specifications》(4th Edition) is worth for each countries to study and is widely taken as a useful specification by more and more countries. This paper mainly compares 《AASHTO LRFD Bridge Design Specification》(4th Edition) with 《Code for Design of Highway Reinforced Concrete and Prestressed Concrete Bridges and Culverts》(JTG D62-2004) and 《General Code for Design of Highway Bridges and Culverts》(JTG D60-2004) and illustrates the result and reason through an example. Due to the complicated contents of the Codes above, the paper focuses on the following points:①The basic principle of bridge design and some related elements are compared. Including the formula and classification of limit states, the requirements of ductility, redundancy and operational importance;②The definition and calculation method of reinforcement and concrete are compared; the comparison of load factor and load classification is included in the paper, so is the design vehicular load, pedestrian load, water loads and wind load. An example is used to illustrate the differences of load between Chinese cods and American specification;③At the part of bearing capacity limit state of prestress concrete, the basic assumption, the formula and the construction requirements of the member in bending, shear, compression and torsion are compared;④At the part of operating limit state of prestress concrete, formula and the construction requirements of crack resistance and deflection of prestress concrete are compared;⑤The result and reason are compared by taking a2-spans continuous girder bridge as an example and analyzing the data which are calculated through the software of CSI Bridge v15.