Comparative Study On The Bridge Specifications Between China And America

《AASHTO LRFD Bridge Design Specifications》is widely used in the overseasprojects, and is taken as an useful reference material for domestic design, scientificresearch, construction and maintenance. Comparison is done between《AASHTOLRFD Bridge Design Specifications》(2007)and《General Code for Design of HighwayBridge and Culverts》(JTG D60-2004)and《Code for Design of Highway ReinforcedConcrete and Prestressed Concrete Bridge and Culverts》(JTG D62-2004)in this paper.Since the codes content is universal, it is difficult to contrast in all details, while thispaper focusing on the following points:①The comparison shows that the basic requirements of bridge structure is thesame for both codes after being compared, but they are expressed in different forms,characterized by the load of the classification, value, load factor, resistance calculationand resistance coefficient;②Materials (such as steel, concrete) are listed, while the comparison of themethods which are applied to determine the strength is done. The compressive strengthof cylinder specimens is directly adopted in AASHTO specifications, while the valueis adopted after transformation of the compressive strength of cube specimens inChinese code;③Two methods applied to compare codes are summarized, method1is realizedby conversion of material strength, by the relationship between the two testingmethods and materials; another method is to adopt the similar material strengthaccording to their respective strength class. Both methods are illustrated in theexamples;④The differences of the calculation method and the formula are found includingbending, shear, beam-column components, and reasons are analyzed. Both thequalitative and quantitative analysis is shown with the examples;⑤After automobile load in AASHTO specifications and Chinese codes beingcalculated respectively to get the effect, both strength and service combinations arecompared by taking a continuous girder bridge as an example; the single load effect islesser AASHTO specifications, but the load coefficient is more, combination effectgradually narrowing gap.