Nonlinear Temperature Distributions in Bridges at Different Locations in the United States

A ti in the case of earthquake loadings or wind loadings which vary significantly throughout the continental United States, a large variation in thermal loadings can be expected. Structures in some parts of the country are more likely to experience large thermal loadings due to specific meteorological conditions. It is not necessary to take the severe conditions experienced in one part of the country into consideration in bridge design for another part of the country where totally different environmental conditions may exist. The current AASHTO Code' deals only marginally with temperature effects in bridge design. The onl y factors addressed are overall expansion and contraction and no adjustments are made for variations in weather conditions through the country other than a distinction between rnoderate'* and cold climates, The two foreign codes that deal extensively with temperature distributions through bridge superstructures are the British BS 5400' and New Zealand Ministry of Works Specifications.' No variation of design conditions with location are suggested by these two codes, since they are intended as specific design guidelines for the British Isles and New Zealand, respectively. The research on which these