Effect of Temperature Variation on the Structural Capacity of a Multi-Span Horizontally Curved Steel I-Girder Bridge

Abstract

Horizontally curved steel I-girder bridges have become a popular bridge design choice among bridge engineers. The current level of knowledge regarding the design and analysis of curved I-girder bridges under thermal loading is incomplete. The thermal expansion of curved bridges is rather complicated and current standards provide little guidance when designing a bearing plan to prevent the development of thermal stresses and out-of-plane distortional behavior. Thermal stresses, in the form of axial compressive stresses, will develop if thermal expansion is constrained. This study examines the effect of different bearing arrangements on the development of thermal stresses and out-of-plane web distortions in a newly constructed bridge located in West Virginia. Three dimensional finite element modeling and analysis is performed in order to predict bridge response. The research shows that uniform thermal loading significantly increases the magnitude of out-ofplane web distortions. Finite element modeling also shows that very significant levels of thermal stress develop in the curved steel I-girders, consuming a considerable percentage of the bridge's total capacity. The web distortions and thermal stresses will result in major serviceability issues, shortening the life of the structure. However, this behavior is largely eliminated with the implementation of a new bearing arrangement, which removes the constraints from the original bearing plan.

Response of Continuous Steel I-Girder Bridges Subject to Temperature Variation

“…The 'rigid link' option in ADINA was utilized to connect the concrete deck to the top flange of the steel I-girders. Simple two-node beam elements were selected to represent the 'W' and 'WT' shape rolled steel cross-frame members (Beckett 2011).…”